failure to send paid up letter

my wife and i settled credit worx account in october. i have callled them repeatedly to ask them to send a paid up letter to [Email Removed] email address but they have failed. as a result i cannot open a new account at the health club for her. they sent it to her old employers email after i repeatedly asked them not to. when we pay a day late they send us sms and call us the whole day but a simple task of sending us this letter seems too much for them to do. i have run out of patience.