Found that if another user has a authorized key set up for another user to access their account usually it can be seen in /.ssh/authorized_keys.
See : https://app.gitbook.com/o/8zAiFgRK6zzhAH9lWN2l/s/fAZp7FYUSvzvoIbLjdkX/~/changes/qTfVkJNHOcRKkez1u9dm/boxes-write-ups/proving-grounds/proving-grounds-practice/moneybox
Enable SSH Server
sudo service ssh start # Enable incoming SSH connections