I disabled all plugins, updated Toolset plugins and WP to 5.8.1 and the weirdest thing happens. When I go to create the post type, the field group displays for a split second and then disappears. I created this video to illustrate:
Sure. Just tell me what you need, if anything, from me. I noticed it after the last plug-in update I did (every plug-in.) I uploaded some files in mid August using this post type without any issues. When I tried in mid September, the issue was there.
I've found the issue. It appears to be a case where you have 2 field groups assigned to the document post type but both field groups have the exact same fields. hidden link
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Ofcourse with the Exception of the Document Title and Document Type fields. When I disabled one of the field groups the fields show up without any issues.
So I would suggest getting rid of the duplicate and combine the fields into one field group.