maas rack controller with duplicate hostname

I have a rack and region controller with name maas which it takes from hostname, today I wanted to add a new rack controller unfortunately I forgot to change hostname and it was configured as maas

So I went through installing rack controller after that I saw I had just overwrite the previous and my fabrics on the primary rack/region controller disappeared.

Would you please add a solution that it gives us a warring that another controller with the same name has already exist on maas?