Girls, What to say, If a girl replies back "What for?" when I ask for her number?

Anonymous
Often girls ask "what for" (both friendly and unfriendly way) when asked for their number. I struggled a lot on that question and couldn't find any matching answer to it. What do you think? what can I say there?
Updates:
+1 y
I don't feel that I should give up if she asks that question. Because some girls are very friendly and full of joy when asking the question. I don't have an answer to give them though.
+1 y
Girls, What to say, If a girl replies back "What for?" when I ask for her number?
Girls, What to say, If a girl replies back "What for?" when I ask for her number?
8
4
Add Opinion