Unable to Sync Database

I have two DT databases which are selected for sync with DTTG. The first database syncs ok; the second one is hung on "Synchronizing items with iCloud (Cloudkit). When I click on the ‘cloud’ icon I see that it is stuck on one file. It was this way last night; this morning I turned off this database and selected ‘clean database’ in DT but no improvement in sync after hours of waiting.

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