if I go out of the program and log back in as a different user
If you are actually closing down the db and logging in as someone else when you get this problem, there's no way you need to "clear the query". There must be something wrong with what/how you're assigning values based on the current user. I think more info around that part of the process needs to be supplied, or you need to check what values are being passed by using temporary message boxes or Debug.Print statements if you can step through what happens after the log in.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.