Switch to using GetUserInfo and populate the query field with the user name (from the InfoPath user name function) on in a form load rule, then run the query. When you set up the data connection, don't set it to run on load. If you are using claims auth, you may need to use a substring-after function to clean up the data returned from the user name function - it is usually easiest to debug if you put the query & data fields on the form, along with a button to run the query, and a calculated value that shows the value returned by the user name function - once you figure out what you need to do, you can clean up the form.
Hilary Stoupa
