diff --git a/app/Services/Invoice/EInvoice/FacturaEInvoice.php b/app/Services/Invoice/EInvoice/FacturaEInvoice.php
index 9f97da9e4519..700bad3602a8 100644
--- a/app/Services/Invoice/EInvoice/FacturaEInvoice.php
+++ b/app/Services/Invoice/EInvoice/FacturaEInvoice.php
@@ -218,8 +218,10 @@ class FacturaEInvoice extends AbstractService
     private function setPoNumber(): self
     {
         $po = $this->invoice->po_number ?? '';
+        $transaction_reference = (isset($this->invoice->custom_value1) && strlen($this->invoice->custom_value1) > 2) ? substr($this->invoice->custom_value1, 0, 20) : null;
+        $contract_reference = (isset($this->invoice->custom_value2) && strlen($this->invoice->custom_value2) > 2) ? $this->invoice->custom_value2: null;
 
-        $this->fac->setReferences($po, substr($this->invoice->custom_value1, 0, 20), $this->invoice->custom_value2);        
+        $this->fac->setReferences($po, $transaction_reference, $contract_reference);        
 
         return $this;
     }
@@ -242,6 +244,9 @@ class FacturaEInvoice extends AbstractService
 
     private function setBillingPeriod(): self
     {
+        if(!$this->invoice->custom_value3)
+            return $this;
+
         try {
             if (\Carbon\Carbon::createFromFormat('Y-m-d', $this->invoice->custom_value3)->format('Y-m-d') === $this->invoice->custom_value3 &&
             \Carbon\Carbon::createFromFormat('Y-m-d', $this->invoice->custom_value4)->format('Y-m-d') === $this->invoice->custom_value4