Very poor customer service

On 10/09/2021 a letter of guarantee was issued in favour of Black Crescent (Pty) Ltd by Q Sales and Marketing in the amount of R100 000.00.(Letter of Guarantee No. ***). In September 2022 both parties agreed to have the guarantee released and that Black Crescent would submit an invoice to ABSA Bank in respect of the amount owed by Q Sales and Marketing and that the remaining balance would be repaid to Q Sales and Marketing. On 18 October I signed an Authorisation to Release the guarantee at the Ladysmith Branch and on 1 November 2022 Black Crescent submitted the Invoice for the oustanding amount to ABSA Ladysmith. Since then the process has stalled as the bank informed Black Crescent that they were required to draft and submit a letter to ABSA bank in a format and with the correct wording that would be acceptable to the bank in order to proceed with the process. I understand that Black Crescent has submitted such draft letter to the bank on two occasions but was informed that it was not acceptable. Now, can somebody please explain to me HOW does the bank expect the client to draft such a letter. Is it not the bank's responsibility to provide the client with the necessary documentation for signature? I'm hereby requesting professional assistance in this matter as it's been draging on for a considerable amount of time and both parties are desperate to have the matter resolved as a matter of urgency.