What are the next steps to take?

My grandma recently tried sending me a package with christmas gifts in there for me and my wife. She put my name on it and almost got my address right but she messed up the apt number. I went to the post office to see what happened and apparently the package was handed directly to the resident of the apartment that my grandma put down. They said they can do nothing but ask the resident to give them the package but they don’t have to. If the post office can retrieve then they will call and return my package to me. Also my grandma forgot to write down a return address. If the package isnt returned, then could i potentially pursue legal action? What should i do next?