Objects with same material react differently to light

Hello people, i have an issue with Unity 2018.1.1f1, when i apply the same material on two different objects, one Object behaves strange. You can see the difference in the picture, the problem seems small but in some levels this problem destroys the whoel atmosphere. If you need more information, i can give it to you. Please let me know if you have any idea how i could possibly fix this issue.