error: unable to write file .git/objects/18/682e3bc1d8d896a6269e7ed6dc4797aa53435f: Permission denied
fatal: failed to write object
fatal: unpack-objects failed
Try to run the following commands to see if they resolve the problem:
If the steps above don't resolve the problem, the repository may be not recoverable. In this case, the situation can be resolved by restoring a backup generated prior to the corruption.