I get the following error message when trying to use the PowerApps Custom Visual in PowerBI services.
Try refreshing your browser.
On my second account the PowerApps Custom Visual works fine. I am also able to edit/view the app on PowerApps app-page.
Which browser do you use? It requires Microsoft Edge or Google Chrome browser to use the PowerApps custom visual, please see the limitations here:
You can't create or modify apps when using the PowerApps custom visual in Power BI desktop, Internet Explorer, or Mozilla Firefox. We recommend that you first publish your report to the Power BI service. Then use Microsoft Edge or Google Chrome to create and update apps.
Best Regards,Qiuyun Yu