Organising pages opens in browser and under a different user

Hi we have an account that has 3 users - one of the users (me) is able to open a PDF then 'organise pages' by selecting that option through the Tool bar - and away I go re-arranging the PDF as I want in Adobe (not online) etc.

Another user has just got a new laptop and has logged in to her account. When SHE goes to 'organise pages' it opens in a browser and is signed in as me with 'learn more' and no option to actually move pages around or delete pages.

We have tried going into 'preferences' and don't have the option to uncheck 'Display PDF in browser'

Please help - its driving me nuts ha!