Hi Tee,
it's impossible that a ReDJ rule behaves different depending on the device type. The rule is based on the URL itself, so if doesn't work from mobile it means that something changes the URL before ReDJ catches it, and the rule doesn't match anymore. Maybe you have a plugin or a template that does something like this (e.g. to adapt the site to mobile views).

I can't say more with my information.

Kind regards,
Luigi