Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
I agree. I have an Office 365 Premium subscription and in Outlook.com I get the blue Upgrade to Premium button. When I click the button, a page appears prompting me to pay for Office 365 Premium, which I have already paid for.
It is total nonsense or else something is very awry with the Microsoft servers if they are unable to link my Outlook.com and Office 365 subscription, both of which use the same Microsoft account.