diff --git a/addons/website_sale/controllers/main.py b/addons/website_sale/controllers/main.py
index a7c9b68d342..1e9d9d52f37 100644
--- a/addons/website_sale/controllers/main.py
+++ b/addons/website_sale/controllers/main.py
@@ -731,13 +731,16 @@ class website_sale(http.Controller):
         # find an already existing transaction
         tx = request.website.sale_get_transaction()
         if tx:
-            if tx.state == 'draft':  # button cliked but no more info -> rewrite on tx or create a new one ?
+            tx_id = tx.id
+            if tx.reference != order.name:
+                tx = False
+                tx_id = False
+            elif tx.state == 'draft':  # button cliked but no more info -> rewrite on tx or create a new one ?
                 tx.write({
                     'acquirer_id': acquirer_id,
                     'amount': order.amount_total,
                 })
-            tx_id = tx.id
-        else:
+        if not tx:
             tx_id = transaction_obj.create(cr, SUPERUSER_ID, {
                 'acquirer_id': acquirer_id,
                 'type': 'form',