2. After chatting for a while and still don't know the name, you can ask: I haven't asked your name yet, so you can't always call me the name I fed. May I know your name? If it's not convenient for you, I'll have to give you a name myself.
When chatting, you can call a girl by any name. When a girl asks if you have mistaken me for someone else, you can say: No, we have been talking for so long, and you haven't told me your name. I think this name fits your temperament very well, so I call it that. You told me the name, and I changed it.
4. If you two have a good chat, tell each other that you want to be friends when you are finished. What's your name? It's natural for the other person to name you. If she didn't give it to you, it wouldn't be embarrassing.