What's the worst gender mix-up you've had?

There are people who play the opposite gender, people who have odd names, and people who just sound like the opposite gender, so I was wondering...

 

What is the worst gender mix-up you've had?

 

I'll go first.

 

I was in a magical theory class, and this guy who was sitting at the desk in front of me decided to message me. We had a short chat, and then he started hitting on me, both of us being guys, and him being straight I assume. So, I took it awkwardly, trying to make it look that I wasn't quite enjoying this, when he decided to ask me if I want to go out on a date with him! I said "You do realize I'm a guy, right?" and then there was the "oh god" from him, and he never talked to me again.

 

So, what is your worst?

When about 5 people started arguing weather Sky was a girl(he is a boy)

does it have to be in this game? 

This one is in real life:
I was about 8, and I was telling my teacher my name in class. I had short, boyish looking hair then, and my teacher thought that I had said that my name was Joey instead of Joy. And cause I hated skirts then, I always wore pants, and all my classmates thought that I was a boy for the first few weeks of school

I was talking to someone, and they kept calling me bro. I was like, hey, that's chill. I'm fine with this. Then: "yo, bro, wanna go hit up some girls?" I was just like... "Er. Not now, actually, haha." How did they think TESSA was a boy?? o-o 

Cassandra doesn't exactly appear to be a boys name. I've honestly never had a large mixup. I'm not sure whether to be happy or sad about that.

Not exactly a mix-up, but at 4 years old I resembled a girl with my hair down to my hip.

The other day i was Skypeing with my friend and he thought i was my brother because i sounded like a boy, and he said so Anderson how's life. I face-palmed so hard.