[Lomak]

when someone purchases something in the store i get this error:
i think Paypal is trying to talk back to the store... I don't use coupons and customer data is mandatory and all field were filled in...

Database error in vBulletin 4.1.0:

Invalid SQL:
UPDATE microcart_usercoupon SET valid=0 WHERE userid=;

MySQL Error   : You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
Error Number  : 1064
Request Date  : Tuesday, January 11th 2011 @ 11:31:27 PM
Error Date    : Tuesday, January 11th 2011 @ 11:31:29 PM
Script        : http://mysite.com/cart_gateway.php?method=paypal
Referrer      : 
IP Address    : 66.211.170.66
Username      : 
Classname     : vB_Database
MySQL Version :