Hi, welcome. Sounds like the speed controller has failed. Craftsman is notorious for not having parts available, but check to see if you have a tool repair shop nearby and let them look at it.
I don't feel comfortable taking tools apart, but you can always check ereplacementparts.com to see if they have this electronic part available, in which case with great care, you might be able to replace the circuit yourself, Good luck with it, many craftsman tools quickly wind up in a recycle bin.
I don't feel comfortable taking tools apart, but you can always check ereplacementparts.com to see if they have this electronic part available, in which case with great care, you might be able to replace the circuit yourself, Good luck with it, many craftsman tools quickly wind up in a recycle bin.