Debit card transaction not finalised

On 28 February 2015 I paid a bill at a coffee shop in Parys with my FNB debit card. The transaction was declined although there were more than sufficient funds in my account. After several attempts the amount was reserved on my bank account and I received an sms to that effect. But still the money was not transferred into the coffee shop's account. Eventually I had to draw cash to pay the bill. After a week the transaction was still not debited to my account and I visited the local FNB branch in Bothaville. The consultant told me the funds were still lying on the magnetic band and all I could do was wait for it to go through and then claim the money back from the coffee shop. It is now two and a half weeks later and still the transaction is not finalized. I do not know what to do any more.