Rogue debit and interest being charged

I received a settlement letter on 11 July for my mobi account and settled immediately to the cent. I have made about 6 calls since to get the account settled. Firstly some funds were allocated to the long term loan. Despite reassurances from many consultants and even received a settlement letter this account has never been updated correctly. I continued to see interest being charged and a small balance showing but consultants insisted balance is zero and no debit expected. Yesterday I was told exactly that as well and that the app will only update after long term loan debit goes off. Today I'm debited for the mobi account. Despite the amount being a smaller amount I should have zero debit and no interest being charged as I have settled this account. How difficult is it for people to understand this and why can't funds be allocated correctly in the first place.Most consultants are clueless and rude as the think they know better .