Do I need to make a purchase to keep my account active?

Question

I received an email saying that my account is going to be deleted because I haven't made any purchases, and if I don't buy something before July, my account will be deleted in August. But I make regular purchases (once every 2 to 3 months) of games, and I don't know why I'm getting this message. Is it some kind of scam that gives you a link, and it looks like it's from an official email because after “@” it says microsoft.com. Is it some kind of phishing attempt or is it real?