OnTriggerExit called automatically after an OnTriggerEnter

I have one object colliding with other, object A with rigidibody and iskinematic with nontrigger collider and object B with collider with istrigger

On objecta A i have a script with the following code. The result is that when objects collide OnTriggerEnter calls automatically OnTriggerExit

Code (CSharp):

1.    
2. private void OnTriggerEnter(Collider other)
3.     {
4.             if (other.GetComponent<ClassObjectB>())
5.             {
6.                 other.GetComponent<ClassObjectB>().collidingWithPlayer = true;
7.             }
8.     }
9.  
10.     private void OnTriggerExit(Collider other)
11.     {
12.             if (other.GetComponent<ClassObjectB>())
13.             {
14.                 other.GetComponent<ClassObjectB>().collidingWithPlayer = false;
15.             }
16.     }
17.