Adding name to active apartment lease

I live in an nyc apartment with my guardian and her son. The apt was put in her name after my parents died when i was a young boy. After they died like i said the apartment was put in her name because my sister and i werent 18 years old. They took my sister and i off the lease when it was put in my guardians name and refuse to put them back because we dont have the same last name. I have lived here all my life. Is it possible to get my name back on the lease?