Cannot access powerbi

Hi All!
I have posted previously but with no luck.. I have got a new work laptop was a HP and is now a DELL. I had 32-bit on the HP and now on DELL I have a 64-bit. I have been trying to open a report I was building on PowerBI Desktop repeatedly with no luck - Unsure as to why and no solutions found on community unfortunately so I thought I would just try to rebuild it brand new. However, as soon as I open PowerBI to build the new report, it keeps instantly coming up with the below message:

Error Message:
We couldn't connect to your DirectQuery data source or internal model. Double-check that your server and database names are correct, and that you have permission to access them.

Please help?!?!