We have had the same error here a few times (again today)
We found that leaving the project and re-joining fixed the problem.
Any lost work was minimal in each case as there has usually been a recent send-receive operation (we train staff to keep their send-receives fairly regular - every 10 minutes or so is usually enough)
ArchiCAD 24 (build 5004)
MacBook Pro (16-inch, 2021) Apple M1 Pro 32GB RAM | MacOS 12.0.1
We ran into this problem a few times last month, and the solution we found, is to create a Travel Pack with users unsent changes, remove this user from the project via the bimcloud manager, then import the Travel Pack.