Same here, but I have Lumia 950 XL. When it tries to show the main page (in the Store app), it is replaced by a "Just a moment..." spinning dialog, then goes to an error page, saying "The Internet is needed here" and gives me an error code and a feedback link. When I click the link, it asks me to sign in with my Microsoft account. I click the account and then "Proceed" (or "Accept"?) and it gives me a black page (standard nav bar on bottom). Never returns from that. I don't have a SIM card in this phone, but WiFi is turned on and connected. This is why I'm now on Android. If it wasn't for Continuum, I would have deep-sixed this by now...