I received a trade in kit, I sent my device, it says it's from Phobio and it looked legit, but now I'm wondering if this is a hoax and they stole my trade-in Mac

Is Phobio a legit Apple trade-in partner? I received the trade-in kit through them and shipped it back to them with the prepaid Fedex label included. Everything seemed to be legit but the Apple page says my kit is still pending to be shipped to me and the Phobio page asks me for an 11-digit trade-in confirmation code. Have they stolen my trade-in Mac?