I'm having some difficulties here

Hi, I was going to add my model into a collection, as I wanna add my model Toyota Starlet Rally Car to my collection TOYOTA which is a part of my collection CARS(containing 70 sub-collections) as when I open the icon of Add to Collection, the drawer opens up, and when I click on right arrow to browse my sub-collections, it shows up 50 sub-collections and in alphabetical order instead of showing more further. do anybody know the alternate method to add models in collection instead of going to model page? even I’ve tried to do the same while using mobile. https://aws1.discourse-cdn.com/sketchup/original/3X/2/4/241fdd1b78681005e69ef33f90ec857948895251.mp4