Query object to String

["seyi103"]

Please I need urgent help. I get my result from a db as a query object and need 
it in my code as a string. I've tried using the ToString() but doesn't seem to 
work and keeps giving me the same error. Argument passed into function is not a 
string. Is there any other way this can be achieved and what am I doing wrong. 
This needs to be demoed tomorrow.
 Thanks