Unauthorized account suspension

Our Business account was blocked through a 3rd Party. FNB blocked our account without a police case number. We were still waiting for our client to give us a credit note, to refund there client's money. The account was blocked just after we received the credit note from our client. We are delivering essentially service while in lock down. FNB never contact us, before locking the account.This happen within 3 to 4 hours. We are FNB client and we feel that they had to look after our interest 1st. Matter is sill not resolved. We sponsored FNB Brakpan with our product. We can not manufacture as we are not able to make payment for raw material.