An empty box was delivered to me

I bought a watch ⌚ on Superbalist on the 24th of March 2022 and it was delivered yesterday 29 March to my surprise when I opened the box 📦 was empty my watch was missing only a small container of the brand of my watch was inside but empty I tried to call them yesterday the whole day to report my case but their line off the whole day. I also sent an email to them but haven't received a response so can anyone help me with this situation. I am their regular customer but this has never happened before