Am I responsible for defamation on my FB group

Yes, even if you don’t know about the comments!

https://openlegal.com.au/am-i-responsible-for-comments-on-my-facebook-page/

How do I keep myself safe ?

I (who am not a lawyer) think that I (as an admin) need to refuse to accept posts that are personal attacks of any kind AND I think this is a solid basis for civil conversations