Sync failes while DTTG 3 is being used

I continuously experience sync failures during data upload to a CloudKit sync store (Log entry: NSCocoaErrorDomain 4097) as soon as I use DTTG 3 (looking through groups, viewing and managing files) during to the process. When I leave it alone it syncs just fine. Occasionally the same error pops up when I use DTTG in Split Screen or Slide Over mode without actually using it. Restarting the device (iPad) didn’t help. Is there something else I could do to prevent that?

To be clear: The files synced at a time up until the error occurs seem fine and sync can be resumed starting with the next batch after that—so the synchronisation process itself seems not compromised, it just stops unexpectedly.

Are these errors logged on iOS or macOS? Which OS version do you use?

Mobile-only setup, iOS/iPadOS 14.3.

Does it work after restarting the apps or rebooting the devices?

I’m still assessing the issue. It definitely got better after a force quit/restart of the App. Rebooting the device lead to no discernible improvement over an app restart. DTTG 3 always becomes sluggish after a dozen or so file operations, regardless of multi tasking (split screen, slide over)—maybe a memory issue? That’s when then sync errors started to spike, also. Right now I am working with DTTG 3 for about an hour and no sync errors occured so far during a large upload task.

For a complete picture: When I reported the error yesterday I was working with both an iCloud (legacy) and an iCloud (CloudKit) sync store for migration. That’s finished now and I shut down the legacy store and received no more error messages, yet.

Follow-up: After migrating and re-syncing two databases from iCloud legacy to CloudKit the problem did not occur again. However, as I already stated DTTG 3 gets more and more sluggish while performing tasks and eventually crashes. Under constant demand (I worked through my databases to check whether the transition went right and to weed out redundant files for several hours yesterday) it kept crashing about two times per hour.

Could you, maybe, send us the Console.log and Sync.log files as well as the crash logs you might find in the iOS Settings app under Privacy > Analytics & Improvements > Analytics Data by email?

That would be no problem. You mean from the day I first reported this (Feb 19th) or all the logs since then (there are quite a few)? What do I put in the subject field?

Select ? > Contact Us and a support email will be created for you to send.

Just the crash logs from the days where it a relevant crash happened. And the logs as suggested by @BLUEFROG.