So, plug it back in, does it show up as a "room" in the controller? If so,
submit a system diagnostic, and
contact Sonos to discuss it. There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.
If it doesn't show up as a "room", then just call Sonos directly, and chat with them.
I am, of course, assuming that you've read the
LED states FAQ
