This article provides a fix for the issue where the new domain redirects to the default domain in the existing or different environment.
The new domain is redirecting to the default domain in the current environment or the default domain of another environment.
It happens when the Variables are not updated after adding a new domain or the wrong Fastly service has been configured in the environment.
bin/magento fastly:conf:get -s
You can find the Fastly API credentials by logging in to each environment (Staging/Production) and checking the /mnt/shared/fastly_tokens.txt
file. For more information, see configure Fastly services in the Commerce on Cloud Infrastructure Guide.
If both the above configurations are correct, submit a support ticket.