Double Transaction

I was logged onto the banking to pay a beneficiary. As I processed the payment and error popped up that they were unable to process the transaction, they are aware of the it and are working to resolve it. I clicked the dismiss button and the payment screen loaded, on the same beneficiary. I noticed that my balance had not changed so I made the payment again. the second payment was successful but I noticed my balance was really low. I quickly checked my transactions, the first "unsuccessful" transaction was actually successful and went through. I went to the closest branch and notified them that I needed to reverse a payment, I explained the situation. they called a certain department and I was told they would investigate and contact the other bank to see if they could recall the money but it would take 14 days and I would be charged a recall fee and they were not certain if they would be able to recall the money.

THIS IS UNACCEPTABLE!! I had never made any type of double transaction. an error appeared and I made the payment only because of the error again.