@kalyan kalapala , Apologies for the delay in response. This is expected behavior on enabling A&A in AppService. Please do follow the below steps to overcome this issue,
1.Setup Azure Front Door with a custom domain.
2.In your Azure Front Door backend, make the “Backend host header” empty. This will propagate your custom domain as the HOST header, which is what Easy AUTH uses to redirect.
3.Add https:///.auth/login/aad/callback to your list of Redirect URLs on your AAD app registration.
Now, if a customer visits your custom domain, they will be redirected back to your custom domain.
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