FNB treated me so badly with my overdraft account

FNB treated me so badly with my overdraft account. I requested a settlement amount and they sent me a settlement letter that say I need to settle the account by the end of June 2021. Now I do not have access to pay the account, I went to the teller, she couldn't, I tried the ATM, the deposit was unsuccessful, when I went back to Zinhle Sijeku, he was so unprofessional , he told me that he is not sure if I am doing it or not. I then asked Zinhle to put me through his manager, he left me holding for more than an hour and disappeared