Annoyed and frustrated

I app**** for an FNB credit card a few months ago but it was not approved. Despite it being not approved, they loaded a card/account onto my fnb banking app. Immediately I requested they remove it, but they were unhelpful and did nothing. Last week, I phoned them twice to request they remove the account, but still nothing. Today I went onto my app, not only is the account still there they are charging me credit card fees and interest for a non existent account. It's absolutely pathetic that such a well-known bank can be so ***********! I am disgusted, frustrated and super annoyed because I don't know what else to do. I've made numerous calls (all from my cell phone), sent countless emails and even went directly to the branch, all to no avail.