Hi @Antonio_Gomez ,
For the report server, dashboard is not a supported feature for it. Check this idea, it is still a feature to be updated.
I guess by dashboard you mean report, when configured with a scheduled refresh the data is not displayed in the report, right?
First refer to the following steps and common information about configuring Power BI report server for scheduled refresh.
Troubleshoot scheduled refresh in Power BI Report Server - Power BI | Microsoft Docs
Configuring Power BI Scheduled Refresh Simplified: 8 Simple Steps (hevodata.com)
If the problem is still not resolved, please provide detailed error information and related operation screenshoots. Looking forward to your reply.
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.