When you clean, you need to make sure you are wiping all of the windows, and some of them are pretty well hidden. There are instructions here on what to clean and how often. (If you are running that thing for 8 hours a day, it’s going to need frequent cleaning to keep it cutting through…might be part of the problem.) The other thing to check is that the material is always pinned down flat…use the Honeycomb Pins.
Make sure your air assist fan is blowing strong. You should see the smoke and flames blow forward towards the front of the machine when the job is running. If you don’t see that, you might need to clean the air assist fan. Instructions for that are here.