One of my developers sent his SSH keys, so I can add to Github.
I get the message "The key is already in use."
How can i fix this?
He already has a GitHub account. Do not add the key, add its account (Admin / Collaborators).
If a developer wants to use different identifiers for different projects, Jasmina Atanasova writes , gives the answer: how to configure different SSH keys for different identities.