Scag won't stay running

Hello I have scag
stt61 Ch, with a kohler engine. The engine will only run when the ignition key is in the start position, if I release it to the run position, motor dies immediately.

Checked all my fuses , just happened out of the blue?

Kohler numbers

Family. Skh624uig2ra
Model. Ch22s
Spec 66546
Serial. 2731100191


Thanks for the help!!


chuck