Contract cancellation

I called in on the 23rd and spoke to Nonhlanhla requesting to cancel my contract as it is coming to an end in Jan 2025, she confirmed that it will be cancelled and I requested she sends me confirmation via email and she said she will. Days went by and I did not get any cancellation confirmation, went to the store and they advised that it was not cancelled instead it was migrated to a red flexi 0 which was not my request, days later I get a migration quotation, still something I did not request. I DO NOT WISH TO BE RETAINED AND WOULD LIKE TO COMPLETELY CANCEL MY CONTRACT AND OPT OF THE RED FLEXI 0!!!!!