Why does the Field Type > DUE DATE shows unknown but the DATE/TIME field works?

[ChuanYanF]

Dear experts,

I want to setup a due date field for an activity but when I create a new column and select the field type which is due date it shows UKNOWN in my form, whereas when I changed it to Date/Time, the UNKNOWN is gone and the field is working like a data and time but does it work like the due date which was my intention at first? Waiting for advise thank you.

[Mark Manders]

How did you setup the field? Did you put a default value in it, or some logic that auto-fills it? Because an empty field will not show 'unknown'. I think you need to check on what is filling the field.

[ChuanYanF]

It is a system default field where I did not create it myself, I just add the fields into the form, but it shows UNKNOWN, but for date/time fields it works just not working for the due date fields which the field type is due date and not date/time

[Jacques Clement]

It's a default out of the box behavior:
"Activity Due" field is not populating any values / Unknown - Support and Troubleshooting