dashboard not visible

Hi RubeS - as shared error, can you check at pbi services level 

Go to Power BI Service>>Navigate to the workspace where the dashboard is published.>>Find the dataset tied to the dashboard and click on the three dots (...).>>Select Settings.>>Under Data source credentials, check if the credentials for the CDS/Dynamics 365 source are valid.>>If the credentials are expired or incorrect, click Edit credentials and update them. Use OAuth2 or the appropriate authentication method depending on how your connection is set up.

Sometimes Power BI dashboards use the credentials of the person who published the report. In such cases, you can re-publish the dashboard with the updated credentials.check under the Permissions tab to ensure that the users who cannot view the dashboard have at least Viewer access.

ref:similar thread.

If you’re using an on-premises data gateway to connect to CDS/Dynamics 365, ensure that the gateway is up and running and that it has the correct credentials configured to access the data source.

Solved: The credentials provided for the PowerBI source ar... - Microsoft Fabric Community

Dataset settings - Microsoft Fabric Community