Exceptionally Annoyed

I have a brand new Samsung A26. Suddenly it gave an error and would not charge. The phone is still under warranty, so was sent away for an assessment. Phone was sent back and I was told they did nothing. The battery lasted a day, and when wanting to charge gave the error again. After numerous attempts took the phone back to MTN. They tested it and it did the same. Yesterday heard that my warranty is rejected, but no reason. Phoned MTN Shelly Beach and asked to get me information and let me know what I am supposed to do with a brand new "broken" phone. Would've phoned me back but never did. Today, 10 April 2026 I tried to phone them multiple times, but nobody is even answering. I have been with MTN for over 20 years on contract and this is not fair and most certainly not good service.