Moving folders is not supported yet. Deselect folders to move files only
Bulk move returned 400 because one or more selected items are folders (movingFoldersIsNotSupportedYet). Member API file-ops may return a shorter Moving folders is not supported yet.
Why this happens
Product only relocates files between parent paths for now; folders stay put.
Diagnose and fix
1. Clear folder checkboxes; keep files selected.
2. Choose a valid destination folder.
3. Retry move.
4. See Move failed if the UI shows the generic error instead.