Page naming regex configuration not working

[CommunityUser]

I'm trying to implement page naming by a regex match on the url but EUM just reports it as empty page name. I just want what the value from arg12=___ When I run my url through regex101.com it works fine. Has anyone tried this?

URL: https://ftp4ABC.ABC.com/human.aspx?r=1891951895&arg12=groups

regex: (a|A)rg12=(.*\r?) 

Regex101 shows my group 2 as fetching "groups" from the arg12= but appdy does not seem to be capturing anything. 

[jeremyGoldstein]

We had a similar issue with our AJAX naming rules. 

Try this:    .*arg12\=([a-zA-Z0-9\_]*).*