PAYING OFF MY CREDIT CARD BECAME A NIGHTMARE

So I have an Amex credit card, I used to pay for this card on time and all until covid hit and I was left unemployed, I communicated with the bank and made arrangements, to my surprise I received summons and I was handed over even though I made arrangements, fast forward to today, I called Nedbank requesting for a settlement amount which their agent advised me that I will get 20% off should I be able to pay off the account in 7 days. on Friday I called to request the letter for settlement to my surprise I was told that the 20% I was told about does not exist. i have been calling the whole day being taken from pillar to post. all i want is to pay up this account and cut ties with Nedbank, I want to go as far as close my cheque account with them, i am done with this bank. I asked them to listen to the recording of my call on Thursday but to this moment I am still waiting for a mere feedback.