diff --git a/VERSION.txt b/VERSION.txt
index b26261575073..62f9457511f8 100644
--- a/VERSION.txt
+++ b/VERSION.txt
@@ -1 +1 @@
-5.5.15
\ No newline at end of file
+6
\ No newline at end of file
diff --git a/app/Http/Controllers/ClientPortal/CreditController.php b/app/Http/Controllers/ClientPortal/CreditController.php
index 9b6ee3fefed8..c49606ae700e 100644
--- a/app/Http/Controllers/ClientPortal/CreditController.php
+++ b/app/Http/Controllers/ClientPortal/CreditController.php
@@ -35,6 +35,7 @@ class CreditController extends Controller
         $data = [
             'credit' => $credit,
             'key' => $invitation ? $invitation->key : false,
+            'invitation' => $invitation
         ];
 
         if ($invitation && auth()->guard('contact') && ! request()->has('silent') && ! $invitation->viewed_date) {
diff --git a/app/Http/Controllers/ClientPortal/InvoiceController.php b/app/Http/Controllers/ClientPortal/InvoiceController.php
index b5f42beb0783..2270a5f8350e 100644
--- a/app/Http/Controllers/ClientPortal/InvoiceController.php
+++ b/app/Http/Controllers/ClientPortal/InvoiceController.php
@@ -69,6 +69,7 @@ class InvoiceController extends Controller
 
         $data = [
             'invoice' => $invoice,
+            'invitation' => $invitation,
             'key' => $invitation ? $invitation->key : false,
         ];
 
diff --git a/app/Http/Controllers/ClientPortal/QuoteController.php b/app/Http/Controllers/ClientPortal/QuoteController.php
index 8cf4d3d9a06f..ccaa48f98e57 100644
--- a/app/Http/Controllers/ClientPortal/QuoteController.php
+++ b/app/Http/Controllers/ClientPortal/QuoteController.php
@@ -61,6 +61,7 @@ class QuoteController extends Controller
         $data = [
             'quote' => $quote,
             'key' => $invitation ? $invitation->key : false,
+            'invitation' => $invitation
         ];
 
         if ($invitation && auth()->guard('contact') && ! request()->has('silent') && ! $invitation->viewed_date) {
diff --git a/app/Http/Controllers/VendorPortal/PurchaseOrderController.php b/app/Http/Controllers/VendorPortal/PurchaseOrderController.php
index a0361a6a09a9..ba2524bf0829 100644
--- a/app/Http/Controllers/VendorPortal/PurchaseOrderController.php
+++ b/app/Http/Controllers/VendorPortal/PurchaseOrderController.php
@@ -99,6 +99,7 @@ class PurchaseOrderController extends Controller
             'settings' => $purchase_order->company->settings,
             'sidebar' => $this->sidebarMenu(),
             'company' => $purchase_order->company,
+            'invitation' => $invitation
         ];
 
         if ($request->query('mode') === 'fullscreen') {
diff --git a/app/Http/Livewire/QuotesTable.php b/app/Http/Livewire/QuotesTable.php
index a82f72898210..4600a0f7a9d9 100644
--- a/app/Http/Livewire/QuotesTable.php
+++ b/app/Http/Livewire/QuotesTable.php
@@ -28,17 +28,17 @@ class QuotesTable extends Component
 
     public $company;
 
-    public $sort_field = 'status_id'; // Default sortBy. Feel free to change or pull from client/company settings.
+    public $sort = 'status_id'; // Default sortBy. Feel free to change or pull from client/company settings.
 
     public $sort_asc = true;
 
     public function sortBy($field)
     {
-        $this->sort_field === $field
+        $this->sort === $field
             ? $this->sort_asc = ! $this->sort_asc
             : $this->sort_asc = true;
 
-        $this->sort_field = $field;
+        $this->sort = $field;
     }
 
     public function mount()
@@ -51,7 +51,7 @@ class QuotesTable extends Component
 
         $query = Quote::query()
             ->with('client.gateway_tokens', 'company', 'client.contacts')
-            ->orderBy($this->sort_field, $this->sort_asc ? 'asc' : 'desc');
+            ->orderBy($this->sort, $this->sort_asc ? 'asc' : 'desc');
 
         if (count($this->status) > 0) {
 
diff --git a/app/Http/ValidationRules/Credit/ValidCreditsRules.php b/app/Http/ValidationRules/Credit/ValidCreditsRules.php
index f745092fe967..b8d6d2624ed8 100644
--- a/app/Http/ValidationRules/Credit/ValidCreditsRules.php
+++ b/app/Http/ValidationRules/Credit/ValidCreditsRules.php
@@ -51,6 +51,15 @@ class ValidCreditsRules implements Rule
 
         $unique_array = [];
         
+        $total_credit_amount = array_sum(array_column($this->input['credits'], 'amount'));
+
+        if($total_credit_amount <= 0){
+
+            $this->error_msg = "Total of credits must be more than zero.";
+
+            return false;
+        }
+
         $cred_collection = Credit::withTrashed()->whereIn('id', array_column($this->input['credits'], 'credit_id'))->get();
 
         foreach ($this->input['credits'] as $credit) {
diff --git a/app/Services/ClientPortal/InstantPayment.php b/app/Services/ClientPortal/InstantPayment.php
index 9ab3dc581e1e..9d03393b2e59 100644
--- a/app/Services/ClientPortal/InstantPayment.php
+++ b/app/Services/ClientPortal/InstantPayment.php
@@ -48,6 +48,7 @@ class InstantPayment
 
     public function run()
     {
+
         $is_credit_payment = false;
 
         $tokens = [];
@@ -107,6 +108,7 @@ class InstantPayment
             $payable_amount = Number::roundValue(Number::parseFloat($payable_invoice['amount'], $client->currency()->precision));
             $invoice_balance = Number::roundValue(($invoice->partial > 0 ? $invoice->partial : $invoice->balance), $client->currency()->precision);
 
+
             /*If we don't allow under/over payments force the payable amount - prevents inspect element adjustments in JS*/
 
             if ($settings->client_portal_allow_under_payment == false && $settings->client_portal_allow_over_payment == false) {
diff --git a/config/ninja.php b/config/ninja.php
index 6bacd49a47f5..d0593cbac99b 100644
--- a/config/ninja.php
+++ b/config/ninja.php
@@ -14,8 +14,8 @@ return [
     'require_https' => env('REQUIRE_HTTPS', true),
     'app_url' => rtrim(env('APP_URL', ''), '/'),
     'app_domain' => env('APP_DOMAIN', 'invoicing.co'),
-    'app_version' => '5.5.15',
-    'app_tag' => '5.5.15',
+    'app_version' => '5.5.16',
+    'app_tag' => '5.5.16',
     'minimum_client_version' => '5.0.16',
     'terms_version' => '1.0.1',
     'api_secret' => env('API_SECRET', ''),
diff --git a/resources/views/email/template/admin.blade.php b/resources/views/email/template/admin.blade.php
index b8f76ee34817..86e7cde9ed47 100644
--- a/resources/views/email/template/admin.blade.php
+++ b/resources/views/email/template/admin.blade.php
@@ -125,7 +125,7 @@
                             <img src="{{ $logo ?? '' }}" alt="" width="155" border="0" align="middle" style="display:block;" />
                             <div style="mso-hide:all;">
                             <![endif]-->
-                            <img class="logo-light" src="{{ $logo ?? '' }}" alt="" style="margin-top: 10px; max-width: 570px; display: block; margin-left: auto; margin-right: auto;"/>
+                            <img class="logo-light" src="{{ $logo ?? '' }}" alt="" width="400" style="margin-top: 10px; max-width: 570px; display: block; margin-left: auto; margin-right: auto;"/>
                             <!--[if gte mso 9]>
                             </div>
                             <![endif]-->
diff --git a/resources/views/email/template/client.blade.php b/resources/views/email/template/client.blade.php
index 7265d4a14168..eb79157f48aa 100644
--- a/resources/views/email/template/client.blade.php
+++ b/resources/views/email/template/client.blade.php
@@ -81,6 +81,15 @@
             text-align: left !important;
         }
     </style>
+
+    <!--[if gte mso 9]>
+    <xml>
+        <o:OfficeDocumentSettings>
+        <o:AllowPNG/>
+        <o:PixelsPerInch>96</o:PixelsPerInch>
+        </o:OfficeDocumentSettings>
+    </xml>
+    <![endif]-->
 </head>
 
 <body
@@ -102,7 +111,7 @@
                             <img src="{{ $logo ?? '' }}" alt="" width="400" border="0" align="middle" style="display:block;" />
                             <div style="mso-hide:all;">
                             <![endif]-->
-                            <img src="{{ $logo ?? '' }}" alt="" style="margin-top: 40px; max-width: 155px; display: block; margin-left: auto; margin-right: auto;"/>
+                            <img src="{{ $logo ?? '' }}" alt="" width="400" style="margin-top: 40px; max-width: 155px; display: block; margin-left: auto; margin-right: auto;"/>
                             <!--[if gte mso 9]>
                             </div>
                             <![endif]-->
diff --git a/resources/views/portal/ninja2020/components/pdf-viewer.blade.php b/resources/views/portal/ninja2020/components/pdf-viewer.blade.php
index ef1bcef4ec0d..9ef7d22ba57b 100644
--- a/resources/views/portal/ninja2020/components/pdf-viewer.blade.php
+++ b/resources/views/portal/ninja2020/components/pdf-viewer.blade.php
@@ -3,7 +3,7 @@
 @endphp
 
 @push('head')
-    <meta name="pdf-url" content="{{ $url ?? $entity->pdf_file_path(null, 'url', true) }}?cache_buster={{time()}}">
+    <meta name="pdf-url" content="{{ $url ?? $entity->pdf_file_path($invitation, 'url', true) }}?cache_buster={{time()}}">
     <script src="{{ asset('js/vendor/pdf.js/pdf.min.js') }}"></script>
 @endpush
 
@@ -86,7 +86,7 @@
         <canvas id="pdf-placeholder" class="shadow rounded-lg bg-white"></canvas>
     </div>
 @else
-    <iframe id="pdf-iframe" src="{{ $url ?? $entity->pdf_file_path(null, 'url', true) }}?cache_buster={{time()}}" class="h-screen w-full border-0 mt-4"></iframe>
+    <iframe id="pdf-iframe" src="{{ $url ?? $entity->pdf_file_path($invitation, 'url', true) }}?cache_buster={{time()}}" class="h-screen w-full border-0 mt-4"></iframe>
 @endif
 
 
diff --git a/resources/views/portal/ninja2020/credits/show.blade.php b/resources/views/portal/ninja2020/credits/show.blade.php
index 0504dce30de7..0d802adc7d79 100644
--- a/resources/views/portal/ninja2020/credits/show.blade.php
+++ b/resources/views/portal/ninja2020/credits/show.blade.php
@@ -33,7 +33,7 @@
 
     @include('portal.ninja2020.components.entity-documents', ['entity' => $credit])
 
-    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $credit])
+    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $credit, 'invitation' => $invitation])
 
     
 @endsection
diff --git a/resources/views/portal/ninja2020/invoices/show-fullscreen.blade.php b/resources/views/portal/ninja2020/invoices/show-fullscreen.blade.php
index f08c3dcff56b..d15cebda832d 100644
--- a/resources/views/portal/ninja2020/invoices/show-fullscreen.blade.php
+++ b/resources/views/portal/ninja2020/invoices/show-fullscreen.blade.php
@@ -1,2 +1,2 @@
-<iframe src="{{ $invoice->pdf_file_path(null, 'url', true) }}"
+<iframe src="{{ $invoice->pdf_file_path($invitation, 'url', true) }}"
         style="position:fixed; top:0; left:0; bottom:0; right:0; width:100%; height:100%; border:none; margin:0; padding:0; overflow:hidden; z-index:999999;"></iframe>
diff --git a/resources/views/portal/ninja2020/invoices/show.blade.php b/resources/views/portal/ninja2020/invoices/show.blade.php
index 168c6f092aa2..6fb066a2ee99 100644
--- a/resources/views/portal/ninja2020/invoices/show.blade.php
+++ b/resources/views/portal/ninja2020/invoices/show.blade.php
@@ -96,7 +96,7 @@
     @endif
 
     @include('portal.ninja2020.components.entity-documents', ['entity' => $invoice])
-    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $invoice])
+    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $invoice, 'invitation' => $invitation])
     @include('portal.ninja2020.invoices.includes.terms', ['entities' => [$invoice], 'entity_type' => ctrans('texts.invoice')])
     @include('portal.ninja2020.invoices.includes.signature')
 @endsection
diff --git a/resources/views/portal/ninja2020/purchase_orders/show.blade.php b/resources/views/portal/ninja2020/purchase_orders/show.blade.php
index 3f9ad02d9722..c95648b5d875 100644
--- a/resources/views/portal/ninja2020/purchase_orders/show.blade.php
+++ b/resources/views/portal/ninja2020/purchase_orders/show.blade.php
@@ -46,7 +46,7 @@
     @endif
 
     @include('portal.ninja2020.components.entity-documents', ['entity' => $purchase_order])
-    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $purchase_order])
+    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $purchase_order, 'invitation' => $invitation])
     @include('portal.ninja2020.invoices.includes.terms', ['entities' => [$purchase_order], 'entity_type' => ctrans('texts.purchase_order')])
     @include('portal.ninja2020.invoices.includes.signature')
 @endsection
diff --git a/resources/views/portal/ninja2020/quotes/show.blade.php b/resources/views/portal/ninja2020/quotes/show.blade.php
index 9e54707f0a5b..fe80c8c6027a 100644
--- a/resources/views/portal/ninja2020/quotes/show.blade.php
+++ b/resources/views/portal/ninja2020/quotes/show.blade.php
@@ -105,7 +105,7 @@
     @endif
 
     @include('portal.ninja2020.components.entity-documents', ['entity' => $quote])
-    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $quote])
+    @include('portal.ninja2020.components.pdf-viewer', ['entity' => $quote, 'invitation' => $invitation])
     @include('portal.ninja2020.invoices.includes.terms', ['entities' => [$quote], 'entity_type' => ctrans('texts.quote')])
     @include('portal.ninja2020.invoices.includes.signature')
 @endsection