How to contact HR?

How would I go about contacting HR about reviewing my background check? I waited 2 weeks for the background check to come back (I'm a felon) and the hiring manager said HR had to review it, they reviewed it but the manager said they only left a green check mark and didn't leave any instructions. So the hiring manager sent them an email about what to do but still haven't heard anything from HR. It's been almost a month and I really need this job for the hours and pay but I can't continue to not work. Is it possible to call and ask? And if so what number would I call?