Some tags converted to groups

I just replaced my MacBook Air with a Mac mini. When I restored my Devonthink databases from the sync store, it converted some (but not all) of the tags into groups of the same name. What did I do wrong? Can I fix this? This affects hundreds of documents. TIA…

There is not enough information to assess here.
Hold the Option key and choose Help > Report bug to start a support ticket and include uncropped, full-resolution screen captures.

Will do. Thanks!