Repository not signed

I’m using ubuntu and have Lulzbot edition of Cura installed on my computer using aleph objects repository. Every time I do an apt-get update I keep getting these messages.

W: The repository ‘ stretch Release’ is not signed.
N: Data from such a repository can’t be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Cura is working fine, but should I be concerned about these messages?

Try adding the key again. Follow the second step in the guide here.

It’s working for others on Ubuntu, so it should be working for you. Let me know how it goes!

Hey thanks for the help it works fine now.