After having downloaded from the website office.com/setup the Office 2019 pro plus version trying to activate it (owning a valid product key) by opening a new word or excel session I do not get prompted the activation steps! Instead a standard word or excel session is opened, under Office 365! I then attempted to uninstall the Office 365 version ... but mysteriously my windows 10 does not find any! I created then a second Microsoft Account e re-attemped the activation of the Office 2019 ... but AGAIN by opening any Office app (an excel sheet in the second attempt) a peacefull new exel sheet under Office 365 was opened denying me again the possibility of activating the Office 2019! I'm going mad! Any help?