The expected finish is empty / is not empty filter does not work as expected

Hello,

Basically my issue is with primavera p6 webclient when I use the filters on the activities view., the expected behavior is this:

 

Say the filter is created to filter only the activities where Expected finish column is empty

 

There are lots of activities where the Expected finish is empty and those are not picked by the filter, hence the defect. The filter simply does not work.

Is there a fix for this?

there is an attached image about it.

regards