Paying Chinese Bills

In China, you pay your utility bill at grocery store. Or maybe the Chinese equivalent of a 7-11. I have to ask my co-worker Sabrina what my mail is. She told me I have a water bill that I need to pay at the 7-11. The bill is for 2 dollars. The trouble is, I couldn't find a market that would take the bill. I guess they need to be approved bill collectors or something. I have been walking around with this two dollar bill for about a week now. I kept going into stores and showing them the bill. They would tell me a bunch of stuff in Chinese and point at the bill. I would nod my head and when it was pretty clear they weren't taking my money, I would say thanks and leave. I have no idea what is going on. I finally found a place about the size of my bedroom that took the bill. I just hope I didn't get scammed for two bucks and have to go to communist jail for not paying my water bill.