Deleted a column, added a column in GSheets, now I can't see the the listing on EnumList.

[Project-APT]

I've got a table, and I decided to remove 2 of the column in Google Sheets and regenerate the table in the app. When I decide to add the column back in Google Sheets, AppSheets registers them into the table when regenerated, however, when trying to change the datatype to EnumList based type Ref, there is not display of the list in the dropdown. But it works with datatype Ref. 

Has anyone encounter this issue before? 

[Steve]

For a column of type EnumList and base type Ref, you must use either Valid If or Suggested values to generate a dropdown of possible values.

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