Changing repository password - "repository is already locked"

I created a repo with a password that I would like to change.
I am entering the command as root

restic -r /var/backup key passwd

and I get the following message

Fatal: unable to create lock in backend: repository is already locked by PID 29883 on omnius by root (UID 0, GID 0)
lock was created at 2018-03-16 04:55:00 (55h39m3.253817054s ago)
storage ID 58303a6b

I get the same message if I try to remove a key

listing and adding keys work

How do I get to remove or change a key?

Thank you

Hey, welcome to the forum! A previous restic process was aborted (probably restic prune or restic forget) and left a lock file in the repo. It’s quite old (55 hours), so you can probably just remove it with restic unlock. Then you should be able to change the password.

When the repository is locked, you cannot do any changes which may remove data (for safety reasons).