Mavis Discount Tire review: Tire service

I had a flat tire less than a month ago I brought my car in for service,
I had a flat tire on the front of the car I have a full size spare, I took the car to Mavis because I herd they bought NTB and I did business with them for over 20 years no issues.

Mavis told me I needed to replace both my front tires which I had no problem with I told them to put the new tires in the rear and the back tires and the back on the front I then said to put the spare back in the trunk,

I never had to check with NTB I knew it was done but 2 weeks later I found the busted tire in the trunk and the new tires on the front, I went back to Mavis and they told me they could not give me back my Michelin tire but they could give a cheaper tire which was unacceptable

I need this resolved