diff --git a/models/account_payment.py b/models/account_payment.py
index 01d8274..2046263 100644
--- a/models/account_payment.py
+++ b/models/account_payment.py
@@ -43,11 +43,13 @@ class AccountPayment(models.Model):
     def write(self, vals):
         """
         Override write to manually trigger synchronization when deductions change.
+        We include 'amount' in the changed_fields to trick Odoo's core sync engine
+        into refreshing the move lines, which will then include the deductions.
         """
         res = super().write(vals)
         if 'deduction_line_ids' in vals or 'amount_substract' in vals:
-            # If deductions change, trigger sync to moves
-            self._synchronize_to_moves({'deduction_line_ids', 'amount_substract'})
+            # Force trigger sync by pretending amount changed if deductions changed
+            self._synchronize_to_moves({'amount', 'deduction_line_ids', 'amount_substract'})
         return res
 
     def action_cancel(self):