Problem with PL-300T00 certification

I'm currently completing the learning path for the PL-300T00 certification regarding Power BI. I'm in the "Data Preparation for Analysis with Power BI" section. The first section of this module is called "Getting Data from Power BI." At the end, there's a space to do a lab. A pop-up window appears. I completed my lab and wanted to continue with the "test your knowledge" section. When I did, the entire certification section got stuck and didn't show any information for taking the test or for another module. Is there a problem, or does anyone know how to fix it?

I've attached images.