Poor service - MTN

I've been struggling with one of my MTN contracts since January 2024 and the matter is still not resolved. Been to 2 MTN shops, called MTN on 135 several times of which this morning was the latest attempt. The call centre agent just told me that she cannot assist me(there is an open ticket on my account) and when asking to speak to a manager, I was told I can call back as they are in a meeting. My contract expired in July already and I just want to cancel the contract - but that is apparently not an option with MTN. On Friday 8/10/2024 a call centre agent promised to call me back, I'm still waiting ....