Ok so I 17F work at an ice cream shop in my town. It's like the towns favorite and it was the first day it was warm out so we had lines wrapped around the building.

Anyways I finsih serving one customer and I go up to the next customers which is about 5 adults and 1 kid who appeared to be about 10.

I say "hello guys how can I help you?" the adults are busy chit chatting away and completely ignore me but the kid speaks up and ask what dairy free ice cream do you guys have.

When someone ask for dairy free we follow the script that the company tells us to which is: "We have our raspberry, mango, and lemon sorbets that are completely dairy free. we also have lactose free ice creams in orange cream and cookies and cream. They are not dairy free but are lactose free." (We offer the lactose free because a lot of people don't have dairy allergies but just are sensitive to lactose and this is a good option for them)

The 10 year old replies that he wants the lactose free of the cookies and cream. We keep the lactose free and sorbets in the back and use proper scooping measures for safety.

I get his scoop and proceed to ask the rest of his family if they want anything. They wave me off.

Fast forward about 45 minutes later a lady storms in and demands to talk to my manager. She points her finger at me and says that she was in with her nephew and that I served him ice cream with dairy. And said that now he is in the emergency room because he is allergic to dairy

I immediately knew what she was talking about and said "maam you or your nephew did not inform me of a dairy allergy. It is ultimately your job to inform of allergy. And I pointed out how she should have been monitoring the nephew order if he was so allergic. I said that I hope her child is ok.

My manager sided with me luckily.

I feel really bad but also I followed the rules. So AITAH?