Can I refuse sustitute service?

I just got told by someone who is trying to serve my roommate court papers (family law) that if they can't get a hold of my roommate then they will substitute serve me... it's the first time I heard of it. I am not a party in this case and I would like no involvement in it whatsoever. So, my question is, can I just kindly tell the person that I refuse to be substitute serviced?