Matching and capturing a date range

I can't get this to match for the life of me. I'm trying to match a date range and inject that into the filename. The date range in the file itself is July 1, 2021 - August 31, 2021

For my rule match I have
Contents > Contain Match >

Code: Select all: December 31,1999 - December 31, 1999

but it doesn't seem to match properly. What am I doing wrong? Is there any way to properly get it to nab a date range with two dates in it?

I'm not sure what you are doing here. Is that a single custom date attribute or multiple? Are you using pattern tokens or did you literally enter "December 31,1999"?