Greyhound: Bus Station

The best thing to do is go immediately to the ticket section and inform them, explain how you missed the bus. Something like your bus arrived after your other bus departed, they may just give you a ticket to get on next bus. If it's because you arrived late for your bus, so it was gone, they may charge a small extra fee to purchase a later time, which is at higher price, so you have to add the difference. I have also seen where, you we're excessively late, so you forfeit your ticket, now have to pay for a whole new ticket. Be honest, you might be surprised, how well it may go for you. 😉

I've already been on the bus just trying to get my bag from the little bait shop in warsaw