Based on your error message, it appears that your front-end page has lost connectivity to this Power BI embedded report. If it is convenient, can you disclose the problem again, is the problem reported every hour or in a smaller interval?
If the problem is that there is an error every hour, then I think it is because the connection is lost due to the expiration of the AAD token used to access the Power BI report embedded in your front-end web page, and you really need to log in again to refresh the token, which is caused by the lifetime of Microsoft Azure's AAD token, you can also check this official document to explore if there is a way to extend the expiration time of this AAD token:
Configurable token lifetimes - Microsoft Entra | Microsoft Learn
If the problem is a continuous error within a smaller interval, then considering that there may be a problem with your local network environment, you can try to use your browser's "Developer tool" to capture the network logs that reported the error for a period of time, and work with your company's network team to further troubleshoot the problem:
How to Collect a Network Trace File from a Browser | IBM
Thank you for your time and sharing, and thank you for your support and understanding of PowerBI!
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly