Asking about something he's not genuinely needing help with as an excuse to even talk to her. This is both a weak and disingenuous way to open a conversation.
Despite her ice cold reaction, he asked for her number straight from the poor opening. Dude is either blind or completely unable to read the most basic of non-verbal cues. Gauging initial reaction is probably the most important part if you're going for cold approaches like this, if it's cold you should just break off immediately, there's no warming up from that.
Looks like this isn't the first time some socially inept dude comes up to her, I can almost hear her thoughts as he goes straight for asking her number after zero rapport "aww, not this sh!t again".
As
@SW15 points out, this didn't work any year.