Could you please guide me how to resolve this issue?
have you followed the steps described here? https://doc.dataiku.com/dss/latest/collaboration/git.html
the way you add a "remote in DSS" depends on if you use HTTPS or SSH interaction mode (https://doc.dataiku.com/dss/latest/collaboration/git.html#working-with-remotes).
You are likely facing the following known issue:
Please try to ssh to firstname.lastname@example.org from the server where DSS is installed using the DSS linux user and then try again. It's important to note that interaction with the remote repositories is always performed by the DSS linux account (e.g. the linux user that installed DSS and is running the corresponding services on the server). Therefore, you should also make sure that the SSH key that you generated corresponds to this DSS linux user.
More information about configuring git remotes in DSS is covered in our documentation here:
Let me know if this helps!