Change Material if overlaps

Hey Guys i got a problem.
Im trying to change a color of an object based on a material that that borders that object. I got a system that spawns grid of flowers
When i click on the flowers im assinging them yellow color, when i click again it returns to blue.
I want to change color of flowers around the yellow to red.
I added a collision box component named triggerbox, I use it to check collisions inside the box. I can make them all change color to red( based on overlapp) when game starts, but im not able to check overlap after i click on a flower, during the gameplay
Can someone help me set it up? Pretty please

I am having the same problem…Did you ever solve it?