I honestly don't know how to handle this when I can't get the info necessary to do my job.

We have a policy that we need two techs in the garage in order to stay open. So if I'm there by myself, we're closed. That ends up happening every night because the tech that I'm supposed to close with (B), seriously just leaves whenever he feels like it. Even if we have customers. That puts me in a position to have to explain to people why we closed early EVERY NIGHT. Customers, managers, whoever. What am I supposed to say? "We're closed because B decided he's tired and wanted to leave"? That doesn't sound professional at all. I don't want to pin it on him but I also don't want it to get pinned on me.

And what about when customers call in the morning and ask when we close? I don't know. I can't predict when B will decide to leave. I asked him today what time he works till and he said, "I don't know. You always ask the dumbest fucking questions. I leave when I leave. If I wanna leave at 4, I'll leave at 4."

I don't have the information necessary to help our paying customers and I don't know what to say when they call.

And no, B is not getting fired. He's worked here for 25 years.