WORST SERVICE EVER RECEIVED FROM ANY BANK!!!

This is really the worst bank that I have ever dealt with and won't recommend them to anyone! After getting a home loan from FNB they told me that if I open a FNB bank account they will give me extra 0.25% discount on my interest rate and only then will they activate my Flexi bond reserve (which was one of my requirements before signing for the home loan). I opened the account within a couple of days after their call and immediately informed the attorneys of the new account details. I have send through my debit order form on 07 July with the FNB banking details where the debit order needs to go off. I changed all my other debit orders and was no longer using my old account. My 1st debit order was supposed to go off 25 September. 25 September FNB tried taking the money from my old account (where there was no money in, because I moved it to FNB as per their request). I immediately transferred the money and also logged complaints for FNB to phone me back, because 2 other calls got cut while talking about the issue and the agent can't even phone back! October FNB AGAIN tried taking money from my previous account, WHICH DID NOT HAVE MONEY IN, BECAUSE EVERYTHING WAS MOVED TO FNB! I now have a bad credit score due to FNB using wrong banking details. FNB is also treating me now with a bad credit score etc. If i don't pay the bond etc. The money is in my FNB account and I have said over the phone and on email that I would gladly transfer the money, as soon as FNB confirms on email that they have cleared my name at the previous bank, my flexi bond will be activated (once I pay this months installment) and that my extra 0.25% will be given off and that they have changed my banking details for the debit order. I still have not received any of this confirmation from FNB, there is still just agents phoning me about the payment due! I have never received this pathetic service from ANY bank before!!! WORST DECISION TO OPEN AN ACCOUNT WITH FNB!