Staff Negligence

In November last year 2022 I took a contract with Telkom they gave me the double deal two phones Samsung A33 phones during my cooling off period I canceled the one phone and I took only one phone I Kindly ask the consultant at the shop to please cancel the other phone and the sim and only make one sim and phone active she did not, the consultant rather gave me a new sim and advised me that I should use the new sim instead. Since then I have been receiving sms saying I owe Telkom R1600 and my contract installment for one phone is R299. So what happend they billing me for 3 sim cards that was supposed to be canceled in November. Yesterday I went to the store in Bryanston as Telkom canceled my line I called the customer care line and I was advised that the cancelation was not made in November for the other sim cards and the phone it was only made yesterday 17 January 2023. They also tried to debit R1600 from my account on the 16th January 2023 and debit was unsuccessful. Dear Telkom please fix this I will not pay the R1600 since u canceled my line I am going to hand in this phone and canceled my contract with you and I am going to make sure I tell my story to each and everyone and warn them abt your bad service. Your staff don't know what they doing. I am very upset 😡