Company says I'm hired but won't call me back

So about a month and a half ago I interviewed for a company, two weeks later they called me telling me that I'm hired that I should come in on the following Monday to do my drug test/put in my paperwork/background check. I didn't hear back from them for a week. I called them up, they said that I passed everything and that I am hired, I just have to wait for a manager to email or call me. Which hasn't happened. I've been trying to call them but the HR guy nor the manager will take my calls.

This is the only job that's said they've hired me, (I have a criminal background thats relatively fresh, I've put in 458 applications and this is the only one who has gotten me this far) I need to get working.

What can I do?

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official