Connection Error: Your file was published but disconnected

Hi, collinq !

Thanks a lot for the answer!

I try to explain better.

I had built a report (properly working), connected to two power bi datasets (properly configured, connected to gateway, data updated regularly, and so on).

For several reasons, I had to remove one of the two power bi datasets, and add a direct data source (basically I imported the data from one of the two power bi datasets, instead of connecting to the dataset). I specify that the imported data has the same origin as the power bi dataset (same db, same server, it's exactly them). So this data source is already configured with the gateway correctly.

Once I did this, the error "One or more cloud data sources for this dataset have been deleted" appeared in the dataset settings. I state that I removed all the data sources that are no longer needed also from the local file before publishing.
This message made it impossible for me to update the data, because it didn't allow me to select the existing gateway. It also asked me to choose a mapping for google sheets as well (which don't need gateways). I've been trying to fix it for days, with no success. So I tried to build the report from zero, assuming a bug.

I created a new pbi file, connected to a power bi data set and to the server directly (I specify that this is not the first time I have done this, there are other reports that work correctly).
When I publish the report locally on the service, I get the error "Your file was published but disconnected" with the same problems described above. Inability to update data, schedule update, select gateway. everything is blocked.

Sorry if I wrote a lot, but I tried to explain better.

Thank you!