10148152, Apologies for the delayed response.
Based on the issue description, I understand you have validated the connectivity between the two WebApps.
- You may always leverage App Service diagnostics from Azure Portal> Navigate to your App Service app in the Azure Portal. (screenshot below)
- In the left navigation, click on
Diagnose and solve problems- Review and run – Network troubleshooter and ““Configuration and Management” (IP address configuration)
- Review Azure App Service access restrictions
Just to confirm, are you able to access your backend web app directly using its default URL from a browser?
To isolate the issue further, please validate these:
- Check if the private endpoint is still linked to the correct private DNS zone and group.
- Check if the private endpoint is still linked to the correct subnet and virtual network.
Kindly let us know, I'll follow-up with you further.