INCOMPETENCE AT ITS BEST!!!!!!

I have a top up contract with one to one its a service used by the TIFG group and it woks with MTN . I cancelled this contract on the 11/09/2019 and they told me they will bill me for October and the number will be prepaid again in October so as soon as my sim card stops working i should contact them and and they will revert it to prepaid . the sim stopped working on the 15/10/2019 I called in and told them and they said it would take 24 to 48 working hours which was 6 days how they calculate it . Till today the sim card is not working one to says i must contact Mtn and Mtn says i must contact one to one im being sent from pillar to post with still feedback calls have being logged i was even ask to do a sim card but that still didnt work . This morining i called again and guess what i need to wait another 6 days so that one to one can log another call to Mtn and for Mtn to respond to them . How does this even begin to make sense