Hello!
I've created a copy of the System Administrator role as I need most but not all the functionality from it for certain users. When I assign the user the System Administrator role, the environment and the app are available.
When I assign the copied role, the app and the environment are not accessible. I've ensured the user is enabled and has license and is a member of the copied role.
I've also done the following:
Add users to an environment automatically or manually - Power Platform | Microsoft Docs
Configure user security in an environment - Power Platform | Microsoft Docs
Thanks for your help