Thanks for the comment, the color of the square in front of the houses actually doesn't matter at all, I was actually going to have it match the color of the mailbox but kind of ran out of time in the jam and prioritized other things. But yeah to deliver packages you have to match the color of at least 1 package you're carrying (shown on the top left) to the mailbox of a house.
Thanks for playing our game and, again, for the comment :)