Get verification emails from AWS account with @mailinator.com root emails

Hi, We do have more than 100 child AWS accounts in this organization. Most of these child account has root email with @mailinator.com domains. Inorder to access the child accounts with root, I first to perform "Forgot Password". But, the problem is: I am not getting forgot password email on any of my child accounts with @mailinator.com domains.

I want to know if AWS is blocking sending emails to @mailinator.com emails. If so, what will be the possible way to access these AWS accounts with root credentials.

Thank you Dipendra