Why did my vinyl top tear open on both sides?

It was 4 yrs old when the seams started to tear, outside of the warranty. The car is parked in an indoor garage with very little exposure to bad weather.

CALL DODGE HEADQUARTERS DIRECT AND TALKK TO A REP THAT MAY HELP YOU.I HAVE HAD GOOD LUCK ADV CUST TO DO THIS AND THEY HAVE HAD GREAT RESULTS.DON'T TAKE THE DEALERS WORD THAT IT IS NOT COVERED

isn't it amazing that no one has sued Mazda people for this junk? I love the car, but this is a disaster. I did pay a ridiculous amount of money to get a new top, but the new top comes with an 8 year warranty. This time, if it tears, I'm going more public than this web site.