Fed Up With MTN

I'm fuming with MTN right now. I've questioning my airtime usage from July 2020. I've been loading R180, R60, R30 airtime almost every month and it goes off as if I loaded R10, Few calls and its gone. I've been following up from July, they tell me they'll call me back to this day I've never received answers or any feedback for that matter. They've confirmed that doesn't go on internet usage as I always have DATA but they are failing to tell me where is going.

On the 9th Sep 2020 I followed up spoke to lady by the name of Nontobeko. She said she could see all the airtime I've been loading, therefore she will escalate my query. I followed up again on 12 Sep 2020 still no feedback.

I called again today 21 Sep 2020 insisted on talking to the manager (Narisha Haril) which took me 55min on the call. Then she tells me their system can not show queries that over 30 days old, she'll escalate my query, then she says she can see that my query was escalated on the 12 Sep 2020 but still no feedback. What must do in order to get answers about all these money I've been spending on MTN airtime?????? I need my airtime to reimbursed ASAP and an explanation how can so much airtime disappear like that and they can't even give me answers for over 2 months. I'm even scared of loading airtime because of all this noncancer.