I booked 2 separate days before and after my travel to the northern. The first day, the staff gave me free upgrade offer when checkin, but charge me when checkout, I told it was free, the manager said he couldn’t find the checkin staff because he was on holiday. So the manager forced me to pay finally. And when I checkin again the second time after come back from the north, checkin staff gave me same upgrade offer, and I refused because my last experience.