Horrible service

I went on to MTN on the 29th of June to upgrade my contract and I took the Vivo V30e and surprisingly when I woke up on the 30th of June it had a middle line on the screen. I went to MTN Monday morning on the 01 July I was told that I need to bring the whole box and everything inside so I can get another phone .

Returned everything on the 8th July and I was told I wouldn't have to wait that long because they just need to check it and give me a new phone.

I have been following up since then with no luck and they no longer taking my calls, then only to get an SMS on the 11 July to state the phone has been repaired I should give it 3-4 days of delivery. How on earth do I get a repaired phone while the phone was still new and had a factory fault so disappointed and I won't be taking a repaired phone only to have issues in the next month