Worst Upgrade Service MTN and Summer Mobile

The worst Company ever I had to interact with. They called me for my upgrade as they work had in hand with MTN but now the devices are not working and they have been collected on the 10th of Oct today is the 31st no one seems to have any concrete feedback they just blame mtn and vice versa. No one wants to take accountability. You send emails they don't respond.. What kind of customer service is that