diff --git a/app/Helpers/Invoice/InvoiceItemSum.php b/app/Helpers/Invoice/InvoiceItemSum.php
index 74625c98416c..b1f7fa9e6471 100644
--- a/app/Helpers/Invoice/InvoiceItemSum.php
+++ b/app/Helpers/Invoice/InvoiceItemSum.php
@@ -144,7 +144,7 @@ class InvoiceItemSum
 
     public function process(): self
     {
-        if (!$this->invoice->line_items || !is_array($this->invoice->line_items)) {
+        if (!$this->invoice->line_items || !is_iterable($this->invoice->line_items)) {
             $this->items = [];
             return $this;
         }
diff --git a/app/Helpers/Invoice/InvoiceItemSumInclusive.php b/app/Helpers/Invoice/InvoiceItemSumInclusive.php
index ad1a92600a08..7198abbfe8d1 100644
--- a/app/Helpers/Invoice/InvoiceItemSumInclusive.php
+++ b/app/Helpers/Invoice/InvoiceItemSumInclusive.php
@@ -131,8 +131,7 @@ class InvoiceItemSumInclusive
 
     public function process()
     {
-        if (! $this->invoice->line_items || ! is_array($this->invoice->line_items) || count($this->invoice->line_items) == 0) {
-
+        if (!$this->invoice->line_items || ! is_iterable($this->invoice->line_items) || count($this->invoice->line_items) == 0) {
             return $this;
         }
 
diff --git a/app/Http/Controllers/ClientPortal/InvoiceController.php b/app/Http/Controllers/ClientPortal/InvoiceController.php
index 3804ab890e94..bbed2ee5bbbf 100644
--- a/app/Http/Controllers/ClientPortal/InvoiceController.php
+++ b/app/Http/Controllers/ClientPortal/InvoiceController.php
@@ -195,7 +195,7 @@ class InvoiceController extends Controller
 
         //format data
         $invoices->map(function ($invoice) {
-            $invoice->service()->removeUnpaidGatewayFees();
+            // $invoice->service()->removeUnpaidGatewayFees();
             $invoice->balance = $invoice->balance > 0 ? Number::formatValue($invoice->balance, $invoice->client->currency()) : 0;
             $invoice->partial = $invoice->partial > 0 ? Number::formatValue($invoice->partial, $invoice->client->currency()) : 0;
 
diff --git a/app/Services/Invoice/AddGatewayFee.php b/app/Services/Invoice/AddGatewayFee.php
index 5729a13195ec..08666ad1f4a5 100644
--- a/app/Services/Invoice/AddGatewayFee.php
+++ b/app/Services/Invoice/AddGatewayFee.php
@@ -29,7 +29,7 @@ class AddGatewayFee extends AbstractService
     {
         $gateway_fee = round($this->company_gateway->calcGatewayFee($this->amount, $this->gateway_type_id, $this->invoice->uses_inclusive_taxes), $this->invoice->client->currency()->precision);
 
-        if (! $gateway_fee) {
+        if (! $gateway_fee || $gateway_fee == 0) {
             return $this->invoice;
         }
 
@@ -52,6 +52,7 @@ class AddGatewayFee extends AbstractService
         $invoice_items = collect($invoice_items)->filter(function ($item) {
             return $item->type_id != '3';
         });
+        // })->toArray();
 
         $this->invoice->line_items = $invoice_items;
 
@@ -150,7 +151,7 @@ class AddGatewayFee extends AbstractService
 
             $this->invoice
             ->ledger()
-            ->updateInvoiceBalance($adjustment * -1, 'Adjustment for adding gateway fee');
+            ->updateInvoiceBalance($adjustment * -1, 'Adjustment for adding gateway DISCOUNT');
         }
 
         return $this->invoice;
diff --git a/app/Services/Invoice/InvoiceService.php b/app/Services/Invoice/InvoiceService.php
index e7d8eb2f6869..7aad51649f2b 100644
--- a/app/Services/Invoice/InvoiceService.php
+++ b/app/Services/Invoice/InvoiceService.php
@@ -402,17 +402,19 @@ class InvoiceService
         $balance = $this->invoice->balance;
 
         //return early if type three does not exist.
-        if (! collect($this->invoice->line_items)->contains('type_id', '3')) {
+        if (! collect($this->invoice->line_items)->contains('type_id', 3)) {
             return $this;
         }
 
         $pre_count = count($this->invoice->line_items);
 
-        $this->invoice->line_items = collect($this->invoice->line_items)
+        $items = collect($this->invoice->line_items)
                                      ->reject(function ($item) {
                                          return $item->type_id == '3';
                                      })->toArray();
 
+        $this->invoice->line_items = array_values($items);
+        
         $this->invoice = $this->invoice->calc()->getInvoice();
         // $this->deletePdf();
         $this->deleteEInvoice();
diff --git a/tests/Unit/LateFeeTest.php b/tests/Unit/LateFeeTest.php
index 5721f79e0727..74c708d0cacd 100644
--- a/tests/Unit/LateFeeTest.php
+++ b/tests/Unit/LateFeeTest.php
@@ -95,6 +95,159 @@ class LateFeeTest extends TestCase
         return $client;
     }
 
+    public function testModelBehaviourInsideMap()
+    {
+        $i = Invoice::factory()->count(5)
+        ->create([
+            'client_id' => $this->client->id,
+            'company_id' => $this->company->id,
+            'user_id' => $this->user->id,
+            'tax_name1' => '',
+            'tax_rate1' => 0,
+            'tax_name2' => '',
+            'tax_rate2' => 0,
+            'tax_name3' => '',
+            'tax_rate3' => 0,
+            'discount' => 0,
+        ]);
+
+        $i->each(function($invoice){
+            $this->assertGreaterThan(1, count($invoice->line_items));
+        });
+
+        $this->assertCount(5, $i);
+
+        $invoices = $i->map(function ($invoice) {
+            $invoice->service()->removeUnpaidGatewayFees();
+            return $invoice;
+        });
+
+        $invoices->each(function ($invoice) {
+            $this->assertGreaterThan(1, count($invoice->line_items));
+        });
+
+        $ids = $invoices->pluck('id');
+
+        $invoices = $i->map(function ($invoice) {
+            
+            $line_items = $invoice->line_items;            
+
+            $item = new InvoiceItem;
+            $item->type_id = '3';
+            $item->product_key = trans('texts.fee');
+            $item->quantity = 1;
+            $item->cost = 10;
+
+            $line_items[] = $item;
+
+            $item = new InvoiceItem;
+            $item->type_id = '5';
+            $item->product_key = trans('texts.fee');
+            $item->quantity = 1;
+            $item->cost = 10;
+
+            $line_items[] = $item;
+            $invoice->line_items = $line_items;
+            $invoice->saveQuietly();
+
+            return $invoice;
+        });
+
+        $invoices = Invoice::whereIn('id', $ids)->cursor()->map(function ($invoice){
+            nlog("line item count = ".count($invoice->line_items));
+            $this->assertGreaterThan(0, count($invoice->line_items));
+            
+            $invoice->service()->removeUnpaidGatewayFees();
+            $invoice = $invoice->fresh();
+            $this->assertGreaterThan(0, count($invoice->line_items));
+
+            return $invoice;
+        });
+
+        $invoices->each(function ($invoice) {
+            nlog($invoice->line_items);
+            $this->assertGreaterThan(0, count($invoice->line_items));
+        });
+
+    }
+
+    public function testCollectionPassesIsArray()
+    {
+        $line_items = collect($this->invoice->line_items);
+        $this->assertTrue(is_array($this->invoice->line_items));
+        $this->assertTrue(is_iterable($line_items));
+        $this->assertFalse(is_array($line_items));
+    }
+
+    public function testLineItemResiliency()
+    {
+        $line_count = count($this->invoice->line_items);
+        $this->assertGreaterThan(0, $line_count);
+
+        $this->invoice->service()->removeUnpaidGatewayFees();
+
+        $this->invoice = $this->invoice->fresh();
+        
+        $this->assertCount($line_count, $this->invoice->line_items);
+    }
+
+    public function testCollectionAsLineItemArray()
+    {
+
+        $i = Invoice::factory()->create([
+            'client_id' => $this->client->id,
+            'company_id' => $this->company->id,
+            'user_id' => $this->user->id,
+            'tax_name1' => '',
+            'tax_rate1' => 0,
+            'tax_name2' => '',
+            'tax_rate2' => 0,
+            'tax_name3' => '',
+            'tax_rate3' => 0,
+            'discount' => 0,
+        ]);
+
+        $line_items = [];
+
+        $item = InvoiceItemFactory::create();
+        $item->quantity = 1;
+        $item->cost = 10;
+        $item->type_id = '1';
+
+        $line_items[] = $item;
+
+        $item = new InvoiceItem;
+        $item->type_id = '5';
+        $item->product_key = trans('texts.fee');
+        $item->quantity = 1;
+        $item->cost = 10;
+
+        $line_items[] = $item;
+
+        $item = InvoiceItemFactory::create();
+        $item->quantity = 1;
+        $item->cost = 1;
+        $item->type_id = '3';
+
+        $line_items[] = $item;
+
+        $i->line_items = $line_items;
+
+        $this->assertEquals(3, count($line_items));
+
+        $i = $i->calc()->getInvoice();
+
+        $this->assertEquals(3, count($i->line_items));
+        $this->assertEquals(21, $i->amount);
+
+        // $invoice_items = collect($invoice_items)->filter(function ($item) {
+        //     return $item->type_id != '3';
+        // });
+
+        // $this->invoice->line_items = $invoice_items;
+
+    }
+
     public function testLateFeeRemovals()
     {
 
@@ -133,6 +286,20 @@ class LateFeeTest extends TestCase
         $cgt->company_gateway_id = $cg->id;
         $cgt->save();
 
+
+        $i = Invoice::factory()->create([
+            'client_id' => $this->client->id,
+            'company_id' => $this->company->id,
+            'user_id' => $this->user->id,
+            'tax_name1' => '',
+            'tax_rate1' => 0,
+            'tax_name2' => '',
+            'tax_rate2' => 0,
+            'tax_name3' => '',
+            'tax_rate3' => 0,
+            'discount' => 0,
+        ]);
+
         $line_items = [];
 
         $item = InvoiceItemFactory::create();
@@ -142,11 +309,11 @@ class LateFeeTest extends TestCase
 
         $line_items[] = $item;
 
-        $invoice_item = new InvoiceItem;
-        $invoice_item->type_id = '5';
-        $invoice_item->product_key = trans('texts.fee');
-        $invoice_item->quantity = 1;
-        $invoice_item->cost = 10;
+        $item = new InvoiceItem;
+        $item->type_id = '5';
+        $item->product_key = trans('texts.fee');
+        $item->quantity = 1;
+        $item->cost = 10;
 
         $line_items[] = $item;
 
@@ -157,20 +324,12 @@ class LateFeeTest extends TestCase
 
         $line_items[] = $item;
 
-        $this->assertTrue(collect($line_items)->contains('type_id', '3'));
-        $this->assertTrue(collect($line_items)->contains('type_id', 3));
-
-        $i = Invoice::factory()->create([
-
-            'client_id' => $this->client->id,
-            'company_id' => $this->company->id,
-            'user_id' => $this->user->id,
-            'line_items' => $line_items,
-        ]);
+        $i->line_items = $line_items;
 
         $i = $i->calc()->getInvoice();
 
         $this->assertEquals(3, count($i->line_items));
+        $this->assertEquals(21, $i->amount);
 
         $invoice_items = (array) $i->line_items;
 
@@ -180,6 +339,10 @@ class LateFeeTest extends TestCase
 
         $i->line_items = $invoice_items;
 
+        $i = $i->calc()->getInvoice();
+
+        $this->assertEquals(20, $i->amount);
+
         $i->line_items = collect($i->line_items)
                                     ->reject(function ($item) {
                                         return $item->type_id == '3';
@@ -192,21 +355,28 @@ class LateFeeTest extends TestCase
         $i = $i->fresh();
 
         $this->assertCount(2, $i->line_items);
+        $this->assertEquals(20, $i->amount);
 
         $line_items = $i->line_items;
 
-        $invoice_item = new InvoiceItem;
-        $invoice_item->type_id = '5';
-        $invoice_item->product_key = trans('texts.fee');
-        $invoice_item->quantity = 1;
-        $invoice_item->cost = 10;
+        $item = new InvoiceItem;
+        $item->type_id = '5';
+        $item->product_key = trans('texts.fee');
+        $item->quantity = 1;
+        $item->cost = 10;
 
         $line_items[] = $item;
 
         $i->line_items = $line_items;
 
         $i = $i->calc()->getInvoice();
+        $this->assertEquals(30, $i->amount);
+        $this->assertCount(3, $i->line_items);
 
+        $i->service()->autoBill();
+        $i = $i->fresh();
+
+        $this->assertEquals(30, $i->amount);
         $this->assertCount(3, $i->line_items);
 
     }