Unhappy !!!!

We had a contract with Nxatel,We had to settle the account in order to use a new Service Provider,We did this paid the monies over to them (+/- R10 000),Then they were still debiting money from our account,that added up to the same amount (+/- R10 000),We have been sending emails\contacting via telephone,since June 2016...And yet it gets referred to many people,no one has tried to help us to sort this matter....What to do? What to do?