19 year relationship ends in ghosting. How do I get my stuff back?

My ex 43m and I 38f were together for 19 years. He ended the relationship by ghosting me. What do I do now? He still has alot of my stuff in his storage unit and he refuses to respond when I reach out to him. I don’t have proof of what he has and I don’t know which storage unit my stuff is in (he has multiple). How do I get my stuff back?

I know he’s physically okay because I spoke with family. But they won’t tell me anything else or get involved.