Honest mistake! Just acknowledge it with them and it'll be easier as you become more mindful of that (:

I’m sure they’ll understand if you talk about it with them, it doesn’t sound like you were meaning to be rude.
I have a stupid question though, if someone wants to be referred to as They, what do you say in this situation? Do you say Excuse me They? Or excuse me You?

When I was training to be a shift I did the same thing to a partner at the store I was training at, and my heart immediately sank so low. I apologized, they were super empathetic because I was in over my head that morning, and we are still friends after my time in their store. Just let them know you care about and respect who they are and as time goes on it’ll just become natural.

I had the same thing happen. Honestly, just communicate with them and let them know it was a slip and that you are aware of thier preferred pronouns and are consciously trying. Usually they will be pretty understanding and appreciate that you are trying your best.

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