problems external sharing

[itelligent-i]

Hi All, I've shared two dashboards with a number of users all who have O365 accounts & tennents for their respective companies.

Non of the users can access the dashboard and there is no reason why this should be the cas, but obviousl I'm missing something.  The reports are built from csv and excel files, but no gateway connectons have been configured.  is this my problem?

An thoughts would be appreciated.