proof of payment

I have requested for a simple proof of payment more than four times from FNB I've yet to receive it. I made a payment yesterday and requested for the proof of payment to be emailed to me. I called three times for the proof of payment the same process was followed confirmation of my email address and I was informed that I was going to be charged for the proof of payment but I ve not received it. I have tried again this morning using a fax number which Im going to be charged for but nothing has come through. All the people I have spoken to telephonically confirm that it has gone through. What will it take for me to really receive this proof? my email and fax number are functioning well as I receive other emails and faxes. I never knew such a simple request could be so difficult to resolve.