Our project administrator is getting "user does not exist when giving permissions to projects that he is a Project Admin on". He is giving permission from the Project - Users screen. He was able to give permissions before. FYI - I was able to add the user myself from the same screen as a subscription administrator.
The Subscription settings do not allow Project Administrators to create new users or Enable and Disable users.
In order for your Project Administrators to have this ability, it will be necessary to flip those fields to True
This link has more detail about the above: https://techdocs.broadcom.com/us/en/ca-enterprise-software/agile-development-and-management/rally-platform-ca-agile-central/rally/administration/configure-your-subscription/customize-your-subscription.html#kj3l0zc3jbs77s4ep6sfvwl4rk79jq_c-customize-your-subscription