OK when was 17 years old I moved in with my cousin we lived in the trailer park and my parents didn't live tofar away so I still seenthem. At the time I had SSI money but since I moved out of my cousins house because hewanted to go to collage I don't even know where it went. He told his mom and dad to tell me that he got a letter from them saying that since they couldn't get ahold of me I lost it. How do I get it back? And what do I do about not having any money at all? I live with my parents and I am 19 years old now and will be 20 in sept. I really need to get my money back because there is a lot I still need.Could I get my cousin in big trouble for this knowing that he was my payee and he knew all about my money and was responsible for this?

If you lost it you can't get it back. If you are still eligible you can open a new claim.
I don't think you can get your cousin in trouble for your losing it but if he spent it on himself and it can be proven then he might be in trouble.
Call SSI ask them where everything stands and about opening a new claim.

You do have to put in a change of address with ss to keep it as well. Call the 800 number chances are all that is needed is that.