diff --git a/models/account_payment.py b/models/account_payment.py
index aed736c..be57fe4 100644
--- a/models/account_payment.py
+++ b/models/account_payment.py
@@ -129,7 +129,10 @@ class AccountPayment(models.Model):
                 # This module creates additional lines that don't fit the standard pattern
                 has_substract = hasattr(pay, 'amount_substract') and pay.amount_substract and pay.amount_substract > 0
                 
-                if not has_substract:
+                # POS Combination Payments can have multiple liquidity lines
+                is_pos_payment = pay._context.get('pos_payment')
+
+                if not has_substract and not is_pos_payment:
                     if len(liquidity_lines) != 1:
                         raise UserError(_(
                             "Journal Entry %s is not valid. In order to proceed, the journal items must "
@@ -161,24 +164,32 @@ class AccountPayment(models.Model):
                         move.display_name,
                     ))
 
-                if counterpart_lines.account_id.account_type == 'asset_receivable':
-                    partner_type = 'customer'
+                if counterpart_lines:
+                    if counterpart_lines[0].account_id.account_type == 'asset_receivable':
+                        partner_type = 'customer'
+                    else:
+                        partner_type = 'supplier'
                 else:
-                    partner_type = 'supplier'
+                    partner_type = 'customer'
 
-                liquidity_amount = liquidity_lines.amount_currency
+                liquidity_amount = sum(liquidity_lines.mapped('amount_currency')) if len(liquidity_lines) > 1 else liquidity_lines.amount_currency
+
+                # Use the first line for currency and partner if multiple
+                first_liquidity_line = liquidity_lines[0] if len(liquidity_lines) > 0 else liquidity_lines
+                
+                if first_liquidity_line:
+                    move_vals_to_write.update({
+                        'currency_id': first_liquidity_line.currency_id.id,
+                        'partner_id': first_liquidity_line.partner_id.id,
+                    })
+                    payment_vals_to_write.update({
+                        'amount': abs(liquidity_amount),
+                        'partner_type': partner_type,
+                        'currency_id': first_liquidity_line.currency_id.id,
+                        'destination_account_id': counterpart_lines[0].account_id.id if counterpart_lines else False,
+                        'partner_id': first_liquidity_line.partner_id.id,
+                    })
 
-                move_vals_to_write.update({
-                    'currency_id': liquidity_lines.currency_id.id,
-                    'partner_id': liquidity_lines.partner_id.id,
-                })
-                payment_vals_to_write.update({
-                    'amount': abs(liquidity_amount),
-                    'partner_type': partner_type,
-                    'currency_id': liquidity_lines.currency_id.id,
-                    'destination_account_id': counterpart_lines.account_id.id,
-                    'partner_id': liquidity_lines.partner_id.id,
-                })
                 if liquidity_amount > 0.0:
                     payment_vals_to_write.update({'payment_type': 'inbound'})
                 elif liquidity_amount < 0.0: