diff --git a/models/payment_transaction.py b/models/payment_transaction.py
index 4921684..7365b3f 100644
--- a/models/payment_transaction.py
+++ b/models/payment_transaction.py
@@ -81,7 +81,10 @@ class PaymentTransaction(models.Model):
                     invoice=self.env['account.move'].sudo().search([('name','=',invoices.name)])
                     reg=self.env['event.registration'].sudo().search(['|','|',('invoice_id','=',invoice.id),('balance_invoice_id','=',invoice.id),('down_payment_invoice_id','=',invoice.id)])
                     if reg:
-                        return 'txR-'+invoice.name
+                        if reg.event_id.booking_event:
+                            return 'txR-'+invoice.name
+                        else:
+                            return 'txP-'+invoice.name
                     else:
                         return 'txP-'+invoice.name
             else: