The girl calls me uncle, do I look that old?

Looking at your photos, I do feel that you are very old. According to your photos, you should be around 70 years old.

So under normal circumstances, it is very normal for a girl to call you uncle.

And if a girl doesn’t call you uncle, it’s obviously rude to her, which means there’s something wrong with her family education. That’s why I suggest you stop chatting with such a girl. That's right, because you strongly suggested that the other person call you uncle, which means that the other person's politeness to you was not exchanged for your politeness, but what you got in exchange was unhappiness.

And I suggest that you should take the initiative to apologize to the girl, because he called you uncle out of politeness, but you did not show polite communication with the other party, so I suggest you Go and apologize to the other party.