Site disconnected and "Public key already set" after server went down

I do use object caching with Memcached via the Lscache plugin (I’m running Litespeed servers). However object caching is set to expire in 6 minutes, so I think if it’s something related to the object cache then it would clear out after this time. But I kept getting the error even after 24 hours.

As for other caches I don’t use a TTL of more than 1 hour.