Hi,
Just check if you have any other accounts logged in the browser? Clear the cache of the browser, logout and relogin to the portal to purchase the license or try incognito mode in the browser. Login to Office.com and confirm if you are using the same account that you created and it is authenticated.
Also try this global numbers so someone can assist you - https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
Hope this helps.
JS
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