Contract Cancellations are a mess

I called MTN to initiate a contract back in Jan-22 and they told me they were out of stock. The lady told me that she'll let me know once she receives stock but she didn't let me know and I just saw a delivery coming in without my approval. I returned the device to a store near me and I got a IRMS number but MTN continued to debit my account. I asked for a refund, but I never got it. I call almost every week and every time it's the same story. I get placed on hold for more than 30 minutes and I eventually hang up cause it's wasteful. I tried contacting them via their twitter channel, all I get is "we'll provide feedback once received". I never thought I'd ever say this, but what a terrible service from one of the leading Telecoms company in Africa.