I fixed mine with a washer and a dab or so of JB weld.
What I did is sanded the washer to give it something to grip to, affixed it to the leftover spot on the tray. When the JB weld setup I popped it over the stub on the bottom tray. I had to sand back the lower tray around the stub a bit so it would go together.
Still holding after 6 years.