I need advices for my JS Calculator project

Hi Campers! I’m recently doing my JS calculator project of Front-end libraries.

This is my project link. I have passed 13 tests but not the num 10, 11, 13.

Do I need to use another way to solve these problems? or Can I improve it from my current code? Which direction would you recommend me to follow?

Any advice would be really appreciated. Thank you in advance.