all posts disappeared & new ones won’t save

I posted this earlier but must have done something wrong because it got marked resolved.

All my posts disappeared this morning. I hadn’t made any changes to code, layout or settings. They don’t show in admin panel but the post and comment counts do. My widgets & format are still okay. Nothing new will save. It was working fine yesterday.

What would cause something like this? My plugins were deactivated a week ago.