As of January of this year, Plus subscriptions have been retired. Please read through this blurb for more info:
Plus subscriptions have been retired and are no longer available. If you were a Plus subscriber, maps you created using your Plus account may look different when you view them. If you used secure or premium content in your maps—such as premium basemaps, Living Atlas reference layers, or infographics cards—this content is replaced with default content included with the standard (free) version of ArcGIS Maps for Power BI. To continue using premium content in your maps, sign in using your ArcGIS Online or ArcGIS Enterprise account. If you don't have an account, sign up for a free trial. Public ArcGIS accounts are not supported.
Maps containing premium content are visible only to ArcGIS users with the appropriate privileges. If you're not signed in to ArcGIS, you'll see a message blocking maps that contain premium or secure content and you'll need to sign in to view the map as it was designed. If you're opening a map-enabled report that does not contain premium or secure content, there's no need to sign in to view and interact with the map.
Please let me know if you have any questions.