Cannot connect to bi data from excel using pro trial

Hi,

I've signed up on pro trial which works fine and I have access to the Power BI webpage which has connected with our organisation data in Xero.  I've also loaded the add-in for excel.  When I try to connect to our Xero data from excel my login creditials are not being recognised through Azure.  My office 365 account shows the Protrial and so does the Power BI webapp page.  Any assistance would be appreciated.

Damien