MTN South Africa

I have been trying to cancel my contract with MTN since 3 July 2021 and up until today 3 March 2021 they keep on deducting premiums from my account . Every time they respond and state they have escalated my compliant to Retentions department. And nothings happens further with my cancelation request .. MTN need to refund my premiums since 3 July 2020 to 3 March 2021 on the date of this .. Now one comes back to you, It feels like an impossible instruction for MTN to handle my cancelation request I send on the 3 July 2020 already!!! Really BAD service from MTN