Most people working for a single organization are unlikely to run into this use case, but if you’re a consultant like me then this issue will annoy you. In Power BI Desktop, authentication against data sources is handled separately from authentication in the Power BI service. This makes sense from an architectural perspective, but leads to a confusing and counter-intuitive user experience.
This means that even though you might be logged into Tenant A from the perspective of publishing into the service (i.e. the top right menu), you will not see Tenant A’s dataflows if you had previously authenticated against Tenant B’s dataflows. “Previously” extends to earlier work sessions in different files.
To resolve this, go to:
Select Global permissions, pick Power BI dataflows, then Edit permissions. You’ll be able to log in with tenant B’s credentials.
Go back to Home > Get Data > Power BI Dataflows, and you will see Tenant B’s workspaces and dataflows. You can now resume doing actual productive work!
Between this and the fact Power BI Desktop doesn’t remember multiple accounts (unlike O365 desktop apps), it’s a bit of a hassle going back and forth between tenants, which I tend to do multiple times a day. There’s a reason why I keep an open browser tab on my password manager!
Related entry: Power BI: The Missing Productivity Features