My Freenas wouldn't connect, beeps 9 and 7 times after restart

[670739]

Hi guys, using freenas 2 years without problem, and this morning can't access to share, retarted my NAS, but it beeps 9 and 7 times after restart and nothing is happening
Please help

 

[670739]

UPDATE
reattached the power cable and removed one of the case back plate and now it works, but I got message:
The boot volume state is DEGRADED: One or more devices could not be opened. Sufficient replicas exist for the pool to continue functioning in a degraded state.
I use 2 ssd's for booting