Date Slicer Between Behavior for null value date

Hi, 

I have the date slicer in my report, and to make it user friendly , I use the between date type so user can easily adjust the date using the scroll bar. 

But for some of the data, the date is null, in this case, I observed belong confusing behavior 

1) Select the date out of the from and to range  (2021/04/06 ~ 2021/12/23 )

1-A): Select the Date-To date later then the max date, the column chart shows all the records  

1-B): Select the Date-From date earlier then the min date, the column chart shows only the not null date records. Data records with whose date is null, are not included in the column chart. 

Then I choose the Start-date (2021/4/6) manually, but the column chart still exclude the two null date value records

2)  Select the date within the from and to range  (2021/04/06 ~ 2021/12/23 )

2-C)  Select the Start Date later then the min date , the data with null date and date not in this new data range are excluded in the column chart 

Then I select the min date again (2021/4/6),  and the column chart has all data back, including the null date records. 

2-D) Select the To-Date earlier then the max date , the data with null date records are still showing on the column chart, but only date not in this new data range are excluded in the column chart 

Then I select the original Date-to , the column chart will show all the records again 

Question: I wanna know what is the logic when dealing with null date value in the data slicer interaction with the visuals on the canvas. Current behavior is very confusing, some cases the null date value records are showing, but some cases not. 

Is that any configurations or options to make sure as long as user select the from-date / to-date to the original one, then the column chart will show all records ? 

Thank you