Account is settled but having trouble on removal of itc between DMC and Capfin

My name is Lindiwe Mokhobo my ID is ********** 681084.I had a loan with Capfin and could not pay as I was not working. I managed to get my finances in order I called Capfin to only find out my account was handed over to DMC.I called DMC for a settlement and amount was given. I paid and was given a proof of payment letter attached above. My query is when TransUnion calls Capfin direct they say the account is still in arrears, as DMC was the third party,and has not communicated with Capfin that this account is paid in full. Without the consent and proof of acknowledgment from DMC to Capfin my account cannot be updated at TransUnion. When I call I get moved from pillar to post I have sent emails and this is hindering me as I need Transunion updated can DMC please tell Capfin that the account has been paid and give Capfin authority to update the account as this is urgent matter.