We arranged a trade. I sent him a package, and gave him the tracking number right after shipping. He confirmed on June 18 that he received the package and that the plants looked nice. It is now July 1, and I have not received anything from him, or heard from him since June 18, despite sending him a message a week ago asking if he had shipped yet and if he could give me a tracking number.

In short, he did not return the trade and has not communicated since receiving the package I sent.