When my Artista 730 starts doing that I know it's time to give it a really good cleaning, ESPECIALLY in the area of the feed. I also remove the throat plate and then clean in the bobbin area, checking for stray snips of threads, and then give it a good oiling. That has always cured my receiving those pesky messages. Oh, I will still receive them, however, if I forget to close the little door to the bobbin area!