Will never use this service provider for contracts

My mum has a contract with MTN, she requested cancellation twice, the contract was supposed to be cancelled on 5-7-2015. We are still waiting for this to happen, you people had a strike but it should not be your clients suffering. When we signed up we were not told there will be sub-standard service if there is a strike so please get contract cancelled ASAP and cancel the debit order, Ref No.: ***