LA115 Blades just stop

Hey all! Needing some direction here before I have to get a bush-hog for cutting yard. This is an issue from last year, so when this started I just used my mower to cut in-laws yard, but was going to try and get the Deere running this year. Father-in-law has a LA115 that the blades will just dis-engage. Stop.

The mower keeps running and going, but cutting will quit.

Thoughts?

I have another bone to pick with this mower but will start in another post.

Thanks for any help here.