Poor service

I have received a business router from mtn on contract on the 25th of July 2020 which is still not working. Many locks have been done. Got 3x people phoning me with the promise to phone back, because fault lies with activation on their side. I am still waiting for the calls back. Even the lady at our store in Beaufort West branch complained that nobody responded back to her. I can't cancel the deal because the 7 day period has expired. My business will be blacklisted. I have received the 1st bill yesterday.