BAD SERVICE

i called cell last week thursday 2017/11/23 requesting a paid up letter as I'm applying for a bond and they need to prove that i dont have a contract with cell c to this day i am still waiting for the paid up letter, i even requested to speak with the supervisor who promised me to speed up the process , that time i was promised that i will get the letter within 24 hours, my bond application is awaiting the letter, might even loose the deal, SO angry ? at cell c for bad customer service, i am never ever getting anything from there, i need the letter ASAP