App Store freezes on opening on a brand new MacBook Air

Hi guys,

I have an issue with my MB Air 10.10.2, which I've bought two days ago. In the beginning I have managed to download couple of apps, but since today when I open my app store, it just freezes, and its all grey, without an option to select anything. Plus the loading symbol shows up, and once I had to hard restart the laptop. Any thought what the issue could be?

Cheers!