MacBook trade-in not received, tracking number unavailable
I have traded in my old MacBook in exchange for a new one. I put the old MacBook in the trade in box, added the label and set up Royal Mail colleciton. My old MacBook was collected by Royal Mail on 25/08/26, but I received a message 04/09/26 that it has not yet been received but the Apple partner. I do not have the tracking number. How can I follow this? Does Apple have the tracking number linked to the trade-in?
MacBook Pro 14″, macOS 26.6