This happened a few months back when I was working at Greenhithe on a late shift.
I was standing on the footbridge about to lock the platform 2 lift up for the night as the station is unmanned after 21:00. A lady came running up the stairs and went to dive straight into the lift, even asked me to hold it for her. I didn’t even think about it, just did as she asked because I’m like that. I even said to her to let me know when she’s out at the bottom so I could lock the lift knowing I wasn’t trapping her in there. She did so, as she was walking back along the platform to make her way back up the stairs (still on platform 2).
She made her way back up the stairs and laughed as she said something along the lines of “That’s not exactly what I meant to do!”. We both laughed as she made her way across the footbridge and down the stairs to platform 1 for her train.