Bad customer service and their not contacable

I have settled my Wonga loan on the 7/11/2022, sameday i have sent a POP and I have also called them they told me the payment will be allocated in 3 days, today i have received a statement my payment was never allocated, I called 6 times at 8:20 was told that their office start at 8:00an but is 8:20 i called again Im not getting through i have sent countless e-mail with no reply i need my settlement letter and they must allocate the payment made to them.