Subreport Linkage

I have a main report that has a subreport.
The link between the 2 is on the phone number.
The main report is using a table that most of the time will have one null phone number that I'm trying to pass to the subreport which is will have a couple null phone numbers that should show up but I'm getting a blank subreport.

Is this even possible??? I've tried a number of different things including making my link on a formula field but doesn't seem to work either.

Any and all help would be greatly appreciated.