How to cancel cricket account service?

ok i got a phone off a guy and the dumb says he cancel the service but when i go down to cricket store to have them switch it over says its still active. So i found out the guys DOB, Address, Full name etc and tryed to disconnect the phone myself, and these stupid *** iraqi people are dumb *** I called 3 times to cancel the account they keep sayings ok the account has been canceled and when i go back to the store they say no the account still active i try recently calling customer care and it keeps going back to the main menu options wtf... anyone know how to solve this problem with out going through the guy i bought it from all his is worried is the money he got from me..