Mtn insurance debited me even after canceling the contract

Mtn insurance debited me for 3 months even after I canceled the contract and I called them and they asked me to email invoices and I did. They told me that they will refund and got nothing, after 4 months I called again and they told me that they will escalate the matter and still nothing. Last month I called again and the consultant told me the same story of escalating the matter and said I will only get one month debit but yet again I'm still waiting