Change "hearts" animation properly with a specific found pair?

How do I make “hearts” to work properly in my game?
I’m using the “pairs” template to try and make a heart animation change with every specific found pair.
Thank you.

My example–

https://drive.google.com/file/d/1fsLdz5WBXb1d4NX20AkZ8k54boHgvFo4/view?usp=sharing