Disgusting behaviour from MTN customer service

Service I have been getting from MTN is disgustingly unprofessional and inconsistent.

1. MTN is claiming I owe money when I do not. I have proof of payment and my account should be up to date. Despite this, my services have now been blocked and I cannot make calls.

2. This follows an unresolved refund issue. MTN acknowledged a refund was due to me and it was paid into my account. Instead of fixing the refund, my line has now been blocked for alleged non-payment.

3. I have contacted MTN call centre several times. The agents were rude, could not confirm any details about my billing or the refund, and were unsure of their own processes. When I asked them to open a formal complaint, they refused.

4. I have sent emails to *** and received no response.

I am now left without service due to MTN's billing error, and with no way to resolve it through normal channels.