Lack of customer service

I received a text message requesting payment to MANCOSA by 25 January 2026. I have been requesting an invoice for some time; however, I have not yet received it. My company is willing to proceed with the payment, but this cannot be done without an official invoice. Each time I follow up with MANCOSA, I am advised that the invoice will be requested and sent to me by close of business. I have been communicating with Suraiya from the Accounts Department, who has been very helpful and responsive. Unfortunately, she has been out of the office for the past two days, and I am awaiting assistance in her absence so that the invoice can be issued.Is she the only person competent at MANCOSA?