Has anyone ever told you to smile because of your resting bitch face?

I have been told once by lady in a grocery store who was the cashier telling me to smile when she never smiled. It made me angry and the next day she told me I had an attitude. I never went to her aisle again. Has it ever occurred to her I might be going through something she doesn't even know about? Allistic people are so clueless and lack empathy. It's a joke to be honest.