In IFS Cloud, I have the following lobby navigation:

page/ChangeRequests/List?$filter=(CrResponsible ne null and CrResponsible eq $[CR_RESPONSIBLE]) or ( CrResponsible eq null)

My desired result is to navigate to ChangeRequests based on the CrResponsible user selected and show all of that repsponsible users Change requests. If you select a line with a null CrResponsible user it is navigating to all the change requests with a null Responsible field (this is working as expected). However, If I select a non null CrReponsible record, It is navigating to all that users change requests + all of the null responsible change requests. 

How do I edit this navigation so that it only navigates to change requests associated with the CrResponsible user selected in the lobby element? and Only navigate to the null CrResponsible values if null record is selected?

Thanks,