On 22 May 2017 (Monday), I was taking a lift at Tower 1. I found that the lift has a missing 'Level 21' button.
I get out of the lift at Level 20, out of curiosity, and went for the staircase to see if the Level 21 is really missing.
Yes, the Level 21 is really missing! Why is the management want to do that? What is the hidden mystery? No one knows. It's kind of spooky when I was at the staircase.