This reminds me of what happened to me many years ago. I was riding a moderately packed tram to school, still half asleep, when a guy came up to me and showed me an ID card. I thought he was a ticket inspector and so I look my pass and showed it to him. He nodded and went away.

Only after a few seconds my brain finally managed to decipher what was written on his card - that he’s disabled. So obviously I jumped up and lead him to my seat with apologies, but I found it hilarious how we both apparently misunderstood each of our ID’s, just in opposite directions.