Issue
I created a private repo in our organization and added an SSH deploy key with write permissions. However, when trying to connect I received a Git configuration error stating that the remote origin was invalid. Upon further investigation, it appears that the RSA keys being generated are SHA-1 which is no longer allowed. I have tried cloning the repo locally with no issues but cannot connect to it. I have been advised to try using the ECDSA key instead.
Resolution
The connection issue occurred because GitHub no longer supports RSA keys that use SHA-1. To fix this, the user generated a new ECDSA key, added it as a deploy key in the repository settings, and updated their SSH configuration. After switching to the ECDSA key, the connection worked without issues. Always use supported key types to ensure compatibility with GitHub.