Incorrect Blocking of account

I have been contacting FNB since last night to unblock an account that they have incorrected blocked at Standard Bank on my behalf and two team leaders and two more consultants have acknowledged this was done in error, however all they have been able to do is send one email and make one call to Standard Bank. I have just spoken to Sello Mathe the complaints manager who has advised that he does not believe there is any fault on their part and I would need to complete an affidavit to unblock the account but only once Standard bank contacts me as they sent the email and can't/won't do anything further. This is the level of service that he is happy with and in turn FNB who he represents...