Below content will remain same for Atomic as well as AX2, except domain name will change for Atomic.
When trying to load the APEXX hosted payment page into an iframe in the Production environment, the page fails to load and displays an error "production.apexxfintech.com refused to connect".
Your subdomain will need to be whitelisted by APEXX Global.
Log a support case listing the subdomain(s) that will host your payment page(s)
We will whitelist the subdomains for you