Pathetic service from Telkom

Had a Telkom landline back in the day. Long story short weathered Telkom line was blown over. After paying for a service which was very much not being provided for a couple of months, we canceled the contract. Telkom is still insiting on "outstanding " payments! Yet they owed us money for the months we paid while waiting for the cancelation to be confirmed. They are not accepting reference numbers as proof. Absolutely ridiculous!