Account closure nightmare!!!!

My credit card migrated to Discovery Bank, first I battled to make payment from my bank account to the card, could not load, then I contacted the helpline to get assistance, I informed the lady that I wanted to close the card and she told me she needs to log a call and within 72hours someone would contact me, this was the 1st of June. I waited very patiently for 72 hours and nobody phoned me back. I phoned the call centre again and spoke to Kingsley Wax, who informed me that he cannot transfer me to a supervisor as they are all in meeting the whole day, the best he can do is sent a request for a supervisor to contact me today still, this was Friday, 05 June. That evening at 18:00 I was still waiting for a call back. I then phones the call centre again, this time I spoke to Tshepo Huma, who again explained to me that he cannot transfer me to a supervisor or manager on duty as their systems does not allow them to do that, I asked for the name of a supervisor as I was getting very agitated, he told me he is escalating my query to Segomotso Nthiti, but more than this he cannot do. Again I had to wait for someone to call me back. Finally late Sunday night Semogotso phoned me back and apologized for the lack of service, and told me he had authorized all on his side and will sent it through for my account to be closed and that I would, latest Monday afternoon receive a conformation of closure letter from them and all would be done. This is now Tuesday afternoon and still no letter from Discovery and no way to get hold of someone to assist!!!! It is impossible to deal with Discovery Bank, there is no client service and the fact you cannot be transferred or be assisted by a supervisor or manager is absurt!!!! Please contact me so I can close my account ASAP!!!!