Starbucks: the final frontier

I have a problem, and it isn't my addiction to dark roast coffee in the mornings.

I can't figure out how to tell the folks at Starbucks (who greet me by my birth name every morning, without fail) my new name. I don't think I need to tell them my new gender identity - that'll get figured out eventually - but I do need to get them to start calling me Jake.

I had a go of it yesterday - after my name change hearing I went in to get a coffee and breakfast and when asked my name for the breakfast item's bag, I said, "Jake."  So he put "Jake" on the bag. No problem.  But this guy was new.

So when the old (as in long-time employee) guy, one of my longest-serving baristas, picked it up to deliver it to me, he said, "Jake! Is there a Jake in the house?"  So I headed over to pick it up and said, "That's me!" and he said, "Oh, okay, "K___."  Epic fail on my part.

I have no idea how to approach this. I know I should say something simple like, "It is Jake now." But they address me first, so I have a difficult time "correcting" them. I know I need to advocate for myself. And I really doubt that Starbucks is going to stop serving me for some irrational reason. But there's something about putting it out there in person that's difficult for me.

Hell, my gold Starbucks card even says "Jake" on it. So what is my problem?