Can't change my plan. There is no 'change plan' button, not on the app, the mobile or desktop site. Not when I enable cookies or visit the exact place I bought it from.I just wanted to upgrade from Premium to Premium Plus(ad-free) but now I may just cancel(through credit card, as there is no option for that either) and encourage others to do the same until you allow access to changing plans easily like every other streaming service in existence. This level of incompetence is shameful.