Bad servicel

I cancel my contract with MTN in September 2022 and MTN kept on billing me even after cancellation of contract they then took my case to debt collectors by the campany called SAYA Recoveries they call me on the 6th September that i owe R1572 to MTN and i paid on 5he same date suprize im being taken from pillar to post with reactivating my number these two campanies are the worse when ot comes to service