What brands do ladies own?
I have a green Olfa mat and a white Dritz mat. I use the Olfa mat constantly and the Dritz maybe once a month for one cut! The Dritz does exactly what you're describing. It does not cut the entire length when the blade is sharp and it cuts just fine on the Olfa. I own it...I use it...not going to just throw it out. I've also used numerous different mats at other places over the course of my quilting years and find non-Olfa mats do the same thing.
If/When I needed to buy another mat it would definitely be an Olfa.
Can you turn your mats over and try the other side?
Nan