It seems that the lift button pressor dulan that another PMA user cut his queue, and since the lift too small to accommodate 2 PMA users, the PMA user who kena cut queue dulan the queue cutter, so keep pressing lift button to waste his time, end up wasting his own time too.
https://mothership.sg/2023/03/pma-user-press-lift-door-button/
https://mothership.sg/2023/03/pma-user-press-lift-door-button/