might there be a "reset" sequence?
for my printer it's press the "stop" "Power" and "maintenance" buttons all at once.
My calculator also had a weird reset sequence that was NOT in the manual.
Maybe try googling for something like that?
At any rate, I'm sorry your machine "stopped" (not my first choice of word, but we've been "encouraged" to keep it polite here).
Are you going through withdrawals?