ApplePayValidateMerchantEvent.validationURL pointing to sandbox url (apple pay)

Hi Team

We are trying to test production domain from local machine for apple pay.

our production domain url is updated according to documentation provided here

https://help.apple.com/developer-account/#/dev1731126fb?sub=dev21822a6b0

But when an applepaysession is getting created and returning ApplePayValidateMerchantEvent, it always returns validationURL as https://apple-pay-gateway-cert.apple.com/paymentservices/startSession

but it should be https://apple-pay-gateway.apple.com/paymentservices/startSession

according to documentation.

here is another documentation for production and test urls

https://developer.apple.com/documentation/apple_pay_on_the_web/setting_up_your_server

Questions

1) How does apple pay session identifies our domain and accordingly returns sandbox or production url ? Does apple pay session validates domain name according to ip address or just domain name?

thanks