UNAUTHORISED DEBIT ORDER DEDUCTIONS BY MTN

I HAVE BEEN A CLIENT OF MTN FOR THE PAST 15 YEARS. I AM ALSO ON THEIR HIGHEST PACKAGE (SKY) AT THE END OF SEPTEMBER 2020 I WAS DOUBLE BILLED AND CALLED MTN CUSTOMER CARE ON 3 OCCASIONS TO REFUND ME . NO REFUND HAS BEEN MADE TO DATE , I HAVE JUST RECEIVED SMS'E FROM MTN EVERY TIME THAT THE MATTER HAS BEEN RESOLVED!! IF I RECALL CORRECTLY I HAD THE SAME PROBLEM LAST YEAR DURING SEPTEMBER .