Simple JS Problem I think, im just being silly

This is my first bash at javascript, and im one function away from finishing.

thetotal = theprice * 2;
thetotal = theprice;

The if else seems to work, i’m fairy sure it’s the thetotal = theprice * 2; that doesnt work. Thanks in advance, you’re my last chance! The entire html is attatched if it makes a difference.