Someone posted a while back that they had a problem with the blades from Harbor Freight but then they cleaned their cutting mat and it made all the difference in the world.
I know cutting mats can get fuzz stuck in them and that might be part of the problem. Or either cutting in the same spot over and over.
I've been more than pleased with my blades from Harbor Freight. I'm on either my second or third from them.
Try cleaning your cutting mat and see if that makes a difference.
Hugs!