I checked in at 5pm and checked out at 7pm. But when I got to the airport, I realized I had bought the wrong ticket. Then I went back to the hotel to continue staying. But the hotel said that if I checked out, I could not stay and had to book another room. I have never encountered a case of buying the wrong ticket, so I don't know if this rule is correct or not! If it is wrong, please forgive me.