diff --git a/odex25_accounting/exp_budget_check/__manifest__.py b/odex25_accounting/exp_budget_check/__manifest__.py
index 225d5b1b7..6a0759a18 100644
--- a/odex25_accounting/exp_budget_check/__manifest__.py
+++ b/odex25_accounting/exp_budget_check/__manifest__.py
@@ -27,6 +27,7 @@
     # always loaded
     'data': [
         'security/security.xml',
+        'data/server_action.xml',
         'views/account_invoice_view.xml',
         'views/hr_expense_view.xml',
     ],
diff --git a/odex25_accounting/exp_budget_check/data/server_action.xml b/odex25_accounting/exp_budget_check/data/server_action.xml
new file mode 100644
index 000000000..749f69dee
--- /dev/null
+++ b/odex25_accounting/exp_budget_check/data/server_action.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+    <record id="server_action_migrate_invoice_rec_id" model="ir.actions.server">
+        <field name="name">Migrate invoice_rec_id to invoice_rec_ids</field>
+        <field name="model_id" ref="base.model_ir_actions_server"/>
+        <field name="state">code</field>
+        <field name="code">
+            env['account.payment'].migrate_invoice_rec_id_to_invoice_rec_ids()
+        </field>
+    </record>
+
+</odoo>
\ No newline at end of file
diff --git a/odex25_accounting/exp_budget_check/models/account_invoice.py b/odex25_accounting/exp_budget_check/models/account_invoice.py
index f1a98124b..7ecf13f4a 100644
--- a/odex25_accounting/exp_budget_check/models/account_invoice.py
+++ b/odex25_accounting/exp_budget_check/models/account_invoice.py
@@ -64,17 +64,21 @@ class AccountMove(models.Model):
     rec_payment_count = fields.Integer(compute='_compute_rec_payment_count', string='# Payments')
 
     def _compute_rec_payment_count(self):
+        # for invoice in self:
+        #     payments = self.env['account.payment'].sudo().search_count([
+        #         ('invoice_rec_id', '=', invoice.id)
+        #     ])
+        #     invoice.rec_payment_count = payments
         for invoice in self:
-            payments = self.env['account.payment'].sudo().search_count([
-                ('invoice_rec_id', '=', invoice.id)
-            ])
-            invoice.rec_payment_count = payments
+            payments = self.env['account.payment'].sudo().search([]).filtered(lambda r: invoice.id in r.invoice_rec_ids)
+            invoice.rec_payment_count = len(payments)
 
     def action_open_related_payment_records(self):
         """ Opens a tree view with related records filtered by a dynamic domain """
-        payments = self.env['account.payment'].search([
-            ('invoice_rec_id', '=', self.id)
-        ]).ids
+        # payments = self.env['account.payment'].search([
+        #     ('invoice_rec_id', '=', self.id)
+        # ]).ids
+        payments = self.env['account.payment'].search([]).filtered(lambda r: self.id in r.invoice_rec_ids).ids
 
         return {
             'name': _('Payments'),
diff --git a/odex25_accounting/exp_budget_check/views/account_invoice_view.xml b/odex25_accounting/exp_budget_check/views/account_invoice_view.xml
index b30989cfd..8b335d37f 100644
--- a/odex25_accounting/exp_budget_check/views/account_invoice_view.xml
+++ b/odex25_accounting/exp_budget_check/views/account_invoice_view.xml
@@ -8,7 +8,7 @@
         <field name="inherit_id" ref="account.view_account_payment_form"/>
         <field name="arch" type="xml">
             <xpath expr="//field[@name='is_matched']" position="after">
-                <field name="invoice_rec_id" invisible="1"/>
+                <field name="invoice_rec_ids" invisible="1"/>
             </xpath>
         </field>
     </record>
diff --git a/odex25_accounting/exp_budget_check/wizard/payment_register.py b/odex25_accounting/exp_budget_check/wizard/payment_register.py
index c369fce29..9eba2625a 100644
--- a/odex25_accounting/exp_budget_check/wizard/payment_register.py
+++ b/odex25_accounting/exp_budget_check/wizard/payment_register.py
@@ -1,4 +1,4 @@
-from odoo import models, fields, _
+from odoo import models, fields, api, _
 from odoo.exceptions import UserError
 
 
@@ -6,6 +6,18 @@ class AccountPayment(models.Model):
     _inherit = "account.payment"
 
     invoice_rec_id = fields.Many2one(comodel_name='account.move', string='Invoice', copy=False)
+    invoice_rec_ids = fields.Many2many(comodel_name='account.move', string='Invoice', copy=False)
+
+
+    @api.model
+    def migrate_invoice_rec_id_to_invoice_rec_ids(self):
+        """Migrates Many2one `invoice_rec_id` to Many2many `invoice_rec_ids`."""
+        records = self.search([('invoice_rec_id', '!=', False)])
+
+        for record in records:
+            record.invoice_rec_ids = [(4, record.invoice_rec_id.id)]  # Add existing ID
+        
+        return f"Migrated {len(records)} records from invoice_rec_id to invoice_rec_ids."
 
 
 class AccountPaymentRegister(models.TransientModel):
@@ -13,11 +25,12 @@ class AccountPaymentRegister(models.TransientModel):
 
     def _create_payments(self):
         self.ensure_one()
-        active_id = self.env.context.get('active_id')
-        if active_id:
-            invoice_payment = self.env['account.payment'].search(
-                [('invoice_rec_id', '=', active_id),
-                 ('state', '=', 'draft')])
+        active_ids = self.env.context.get('active_ids')
+        if active_ids:
+            # invoice_payment = self.env['account.payment'].search(
+            #     [('invoice_rec_id', '=', active_id),
+            #      ('state', '=', 'draft')])
+            invoice_payment = self.env['account.payment'].search([('state', '=', 'draft')]).filtered(lambda r: set(active_ids) & set(r.invoice_rec_ids.ids))
             if invoice_payment:
                 raise UserError(
                     _('You can not create payment for this invoice because there is a draft payment for it'))
@@ -58,7 +71,7 @@ class AccountPaymentRegister(models.TransientModel):
         self._reconcile_payments(process_final, edit_mode=edit_mode)
         for payment in payments:
             if payment.payment_type == 'outbound':
-                payment.invoice_rec_id = active_id
+                payment.invoice_rec_ids = [(4, active_id) for active_id in active_ids]
                 payment.action_cancel()
                 payment.action_draft()
         return payments