FNB is taking me for a ride

I am having trouble with FNB. I was on the process of getting a rent to own car from the rent to own cars owner, we agreed on a deposit fee as I was not the only contester for the vehicle. I made a deposit of R12 500 to him, of which an hour later He called in to say he got a better offer from other contesters, he then refunded R12 500 back to my account. The refund was placed on pledge / hold by FNB as they suspected I received proceeds of alleged *****. FNB required proof of reasons why I received those funds in my account. The only proof I had was proof of payment I did sent the funds, and proof of payment the owner refunded me back, and also his affidavits stating the reasons behind the transaction, and I did sent to the investigator by the name Of Moipone Gumbi of FNB. She later rep**** to me to say they are in the process of refunding the payer, of which 4 days later she sent me an email to say they do not accept proof of payments and affidavits.

I failed to pay my kids school fees, and Also failed to feed them for a month now. Please intervene and have this matter resolved as soon as possible