Are you perhaps talking about replicas?
https://docs.railway.com/reference/scaling

Or are you talking about multiple individual services of the same repo?

One thing I'm encountering is that when I make a new project I cannot make several services of the same repo (monorepo) unless I right click and duplicate the service, then it works fine

Oh, you mean going through that right click -> github repo?

Are you the owner of this monorepo or is it a public repo?

Asking because I was talking with a team member about this, this might be some sort of regression/bug

Yes, owner of the org and it's a private repo

Yup!

I'm assuming that's what this guy meant too so just jumping in here with my experience

Can you show a screenshot of what modal opens up when you right click the canvas and click 'github repo'?

This

I figured out by just duplicating

This breaks if u already deployed it

i mean - nothing happens