Unprofessional , poor customer service

I am not happy with creditworx nimble group they offered me a discount on my standard bank outstanding balance I paid it in now they called and informed me its paid up but they have not sent me a paid up letter to show standard bank so I can close the account I keep calling hold 10 min still no answe mxm very unprofessional they are a nuisance when you've to pay but when you have made a payment they drag and dont give you what's due to you