Variations matter. Can you post actual message? The two numbers are especially relevant.
You might be able to find the error in job logs, or server log at About → Show log → Stored.
If first number is higher, then the Remotevolume State theory may fit. Not sure about lower.
Although that’s not common, there have been reports and also a somewhat contrived repro.
Database inspection sounds like a worthwhile test. If too hard, and DB is not painfully huge,
Create bug report button could download a sanitized DB you can store and post a link to.