call managers are useless!! cancel my line now!

I app**** for an upgrade 25 may 2018. 26 may 2018 returned the device to the store as it heated up. I was turned away and told to come back the monday 28 may 2018 which i did and returned the device. Was told that it needs to be sent away. I booked the phone in and was advised it will reach jhb thursday 21 may 2018. I called headoffice on the 4th june 2018 and spoke to Gary and was advised that according to their system no device was booked in and that i still had the device he said he will email the store to have it delivered urgently. I called retentions and spoke to siphokazi a manager who advised they will cancel effect 4 july 2018 and that the n1 city store manager should call and update their system. Anele advised they had a problem with ram couriers and the device was returned to the shop. I told the manager anele that i dont care they messed up. He said he will contact his manager darryl or david skylar to confirm if he can cancel and if he cant a new device will be given to me. I gave him until the 5 june 2018 and was then advised he cant cancel nor can replace the device as it needs to be tested. He promised that he will send me rams tracking number but till today i have not heard anything from him. He said i will not be liable for any charges and i will not be charged as i dont have the device and have never used the sim. I complained on hello peter and spoke to moses who promised he will monitor and provide me with feedback but i still have not heard anything. I have call recording and voice recordings of all interactions with cellc and will be taking this matter further. Promises were made and not honoured. Not a single manager can assist. I want to cancel. I dont want anything i just want to cancel according to 2 managers at cell c anele and siphokazi i can cancel this pathetic service!!!