Guild Wars 2

I like the song used in vid, can u tell me its full name and artist?

I cant buy anything since the ‘Buy’ button is Grey even if I have enough cash in inventory to buy it. (other conditions like avainablilty at store etc are also present). Im not able to use ‘Place order’ as well. (appearing in grey like above)

Edit: After few game restarts it fixed itself.. x.x