Unauthorised Debit Orders

I'm totally disappointed with FNB's customer services. On the 31st of October 2019 I had an unauthorised Debit Order on my account and I was unable to reverse it on the banking APP/through internet banking due to that the DO is sitting under "transactions" First I went to the branch at Golden Walk in Germiston, they gave me a ticket number and I waited for an hour because the consultants were having a staff meeting. I then went to a branch at forest hill and was told to use the secure chat on my APP to get assistance. I used the secure chat and was told to complete a DO Dispute form and e-mail it. After e-mailing I got a response that the e-mail channel was discontinued and I should use the banking APP(which I have already explained that it is not helping), I went back to the secure chat and the consultants are just taking me back and forth asking me the same questions over and over again. The other consultant asked if I consulted the merchant, how on earth do i know who is the merchant and how do I get hold of them? aren't the consultants supposed to connect me to the relevant person? I'm totally frustrated about the service.