Hi Sandeep Kumar,
As per my understanding from your query, I have provided troubleshooting steps:
The Application Gateway may be misconfigured to route only specific paths correctly while other paths might not be properly routed. Check the path-based routing rules.
If the website uses HTTPS, there may be SSL/TLS certificate configuration issues. Verify that certificate is valid and correctly configured, ensure that the Application Gateway's HTTP settings are configured to use the correct protocol.
Check the Network Security Group and Windows Firewall settings properly.
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