Capitec Bank messing with our livelihood

I have been their client for 17 years now, the sent me a message requesting my proof of income and proof of residence as per FICA requirements.

Submitted that at a branch, a day later the were questioning fund received on my bank account in particular thid one transaction indicated on the email and further indicated that the payslip that I had sent is not sufficient for the transactions that are happening in my account. I sent them invoices proving the monies received as i am employed and also freelancing on the side. The report was that they need more information as I am receiving fund from different sources which doesn't make sen6because the invoices were sent tot them that explains everything.

I feel that this is a plot of ****ing me off of my fixed savings because this doesn't make any sense