NOT HAPPY AT ALL WITH FNB SERVICE

I have been trying to dispute a debit order which was debited to my account after it was cancelled with the company. I have first done a secure chat during the first week of May 2020. I was then told that I have to dispute the debit order on my FNB App. I was given the whole process. Tried to do that, not working. I then went back to secure chat, they told me, no sorry, you have to call the no ***. I have called this number 5 times, every time running out of airtime, because you hold on for more than half an hour at a time. I then drove to FNB Riverside, I was referred to the Manager in the 1st left office. She did something on the computer, said no problem, it was done. Till now, the debit order has not been returned. I send a complaint through with no ***, had not been resolved, this being on 17 June 2020. I honestly don't know what to do to get the service from my Bank that I pay for. The policy no is Liberty Life ***C for R499.17.