Unable to save my schema "Columns data type can't be blank"

Please resolve the following problems to continue:

Columns data type can’t be blank.

Getting the above error when I try to save the schema. Couldn’t figure out what’s missing in the schema. I have checked the data types.

Thanks in advance

Having the same issue here, anyone able to look into this?

tl;dr: remove all “JSON Object” field types and ensure your nested fields are prefixed with the parent field name

Hi, I was having this problem when working with a field list generated from a json schema (using the “Import Fields from JSON” option)
I had several nested JSON Objects, such as “contactDetails” and “contactDetails.homeAddress”. The import process identified these fields as JSON Objects, but that type doesn’t exist when you try and specify it manually (only JSON Array is available).

I tried removing those JSON Object fields and made sure that all the nested field names were fully prefixed, such as “contactDetails.homeAddress.line1”, because some of those were missing.

After I did that I was able to save the schema successfully

Hope this helps someone else