It's been over 21 days now I haven't received my refund. Since I have bills to pay and kids to take care of, I would like to know if a personal case could be opened throughmy Max Benefits, so I

There is no way to speed up the refund. It has to be processed within the IRS system. 

You can track your refund by visiting the Where's My Refund website here. 

If it has been beyond 21 days, you can click here to contact the IRS.