Courier guy- jewel city

I arrived at the shop 15 minutes it’s closure , as a first user of their services I had no idea what I was suppose to do so I waited on the queue. So when I got to the till , before I could say anything the lady said they are closed, I should try and ask ask the guy at the back if he can help me , the guy blatantly tells that they are close. My understanding of closing at five is that you stop giving service at 5 and everyone inside the shop before five must be offered the service.