Applauding Query Unresolved

I had a loan with FNB that I settled the balance before they monthly debit order ran , couple days later when the loan was settled they then deducted R115 on my account for that loan which left my account on a minus , I called 3 times to try and get them to reserve the funds as this was a fault on their part, on all occasions up to now this has not been done. 7 weeks later 3 consultants all didnt get this resolved. I could settle this small amount however because of my effort, time and calls monies spent to have such a big institution not resolve this or even get back to me for feedback its really bad. i have been an FNB client since school over 20 yrs but this really forced me to shop around and look for another bank. FNB resolve this so I can part ways with you. This is the worst service ever, I should have just closed this account the day I went to the bank before this happened.