FNB is horrible when you are trying to switch debit orders

I have been trying to update my my homeloan debit order from my old FNB account to an Absa account since September. My homeloan is currently with FNB, I requested a change on the FNB App in September, then on the 7th of October FNB existing business sent me an email requesting proof of Absa bank account. I sent the proof of bank account on the 7th of October. But today I they are still trying to debit the FNB account.