SHOP BUG( Riot Greighish's helping advice didnt help)

So when I go to the store, Im in the featured section, when i try to go to another in the shop, it doesn't let me and i just get a session expired warning for a second then I go back to the featured. But when I click on a specific button in store repeatedly it lets me go there but doesn't let me buy anything then when i try to go somewhere else in the store, I go back to the recent section where I was. Even if i try to buy it in my profile it either says "Unavailable" or "Your purchase could not be completed at this time. Please fix it I've been missing out for a week.