PHP MySQL ORDER BY level DESC LIMIT 1 not working on all searchs

I have searched for an answer to this problem all over the web and here at Stackoverflow. Nothing seems to help. This should be a very simple function. I have multiple records with the same content EXCEPT a field called level. I want to find the record with the highest int value in level. An example would be that I have multiple records with the same userid and email but the first record starts at level 1, the next may be level 2 and then the next may be level 1 again. I want to find the record with level = 2. My code is very simple.

  $LoginRS__query=sprintf("SELECT userid, email, level FROM orders WHERE userid=%s AND email=%s ORDER BY level DESC LIMIT 1", GetSQLValueString($loginUsername, "text"), GetSQLValueString($password, "text"));

For some this works correctly, returning the record with level = 2, 3, 8, 9, whatever. For others it will only return the record with level = 1. The field level is int length 1. I'm running php Version 5.3.28 and MySQL 5.5.36

Any ideas anyone? Like most, I'm in a rush. Thanks...

via Chebli Mohamed