Non-payment on sale of iPhone

Sold my phone and no response on WhatsApp, on email and calls. No information from Phonetradr at all regarding a sale, except that I can see it says sold on my profile on the site. It is upsetting that a company can take your phone and ignore you when it comes to payment. I am not even hopeful that I will get my money or the phone back. It's been over 3 weeks since it sold and nothing, not even an automated email! Use Bobshop, don't deal with unprofessional unknown companies!