BAD CUSTOMER SERVICES

So I have a loan with FNB and they decided on my behalf for it to be debited weekly instead of monthly as I requested in the 1st place. An amount was debited on the 13th, I paid the remainder of the installment myself then to my surprise another amount is debited on the 20th. Im chatting to advisors who is disconnecting my chats, tranfering my query and no one to assist! Im so disgusted by the service of FNB. I even called in was advised to hold as they trasfer my call, just for them to drop the line. What a waste of time!