Why don't old SSH keys work after OS reinstallation?

Question

git

I reinstalled the OS, returned the keys that were to the .ssh folder.
When I try to clone the project, it says that there is no access and asks for a password

Answer 1

Are the access rights to the rwx keys exactly set?
Usually the rights are viewed with the ls -ls command, and set with chmod, chown, chgrp commands to set the necessary rights, the necessary owner, and, if necessary, the necessary group.