Clammed Room Escape

You have been invited to attend the prestigious event at the pearl of the city, The Clammed Hotel. The hotel was constructed at the late 1900s primarily as the prime residence of the mayor of the city but the order was later revoked and was proposed to be renovated as a hotel. Until this day, it has become a 5-star hotel by the efforts of the management. You were the last one to arrive at the hotel due to the heavy rainfall that caused traffic around the metro. Since you were the last, all the participants are already in the function hall and you were the only one left inside, When you are ready to go the event, you were accidentally locked inside by someone. Find your key or find another way out.