Hi @James_Jancel, welcome to the Asana Community Forum!
To investigate this further, I’d recommend reaching directly to our support team who will be able to take a closer look into this for you! When reaching out, make sure to provide them with the following info, it will facilitate their investigations:
- Confirm the email address you are trying to add
- Confirm the new domain
Sorry for not being able to resolve this specific issue via the forum. Unfortunately I don’t have the tools to have a closer look and verify the domains. If you have any other question in the future feel free to reach out here, in most cases we will be able to resolve your issue, and if not, we’ll be able to redirect you to the right place