TRANSACTION NOT PERMITTED?

I find the issues with FNB mobile banking and online banking to be quite Annoying. I tried to transfer the available balance from my revolving loan to my Cheque Account on the FNB app and keep getting the error "This Transaction is Not Permitted" - that's it, no further info. I spent 12 mins waiting on the line for an FNB consultant then I am transferred from department to department and suddenly the call drops. I've now been trying for days, beyond ridiculous.