Should I just leave?

I just got to work and no one is here, like no other employees, no managers, nothing. I can’t go inside until someone else gets here. I was supposed to be here at 7, it’s now almost 7:30 and still no one has showed up. I don’t have the managers phone number so I’m trying to figure out what I should do? Should I just wait till 8 and then go? I live over a half hour away so I don’t know what I should do!!