This is a fun, relevant take on the theme. The art is pretty cute and the music is delightful to play to!
I did have issues picking op and dropping the items into the garbage bins. I think putting each garbage bin directly on a square and then having the player either be next to or on top of the square to drop garbage into it would help.
I also had trouble remembering which garbage goes into which bin, especially with the limited time to play. Depending on how much of a challenge you want that to be to the player, colour coding the garbage to the correct bins more or adding little symbols to the bins would help the player figure out what needs to go where faster.
Great job, Holes in the Wall was fun to try out!