How to Camera Rotation when UI is up?

Hi,

I am trying to script in a function where the first person controller camera controls is frozen if any UI canvas' are up. I have tried to do this with the script:

     if ((canvas.enabled == true) || (canvas2.enabled == true) ||( canvas3.enabled == true) {
         //DISABLE CAMERA ROTATION
         gameObject.GetComponent<FirstPersonController>().enabled = false;
         
     } else{
         //ENABLE CAMERA ROTATION
         gameObject.GetComponent<FirstPersonController>().enabled = true;

     }

But the issue I get is that the whole mouse function is disabled. As in, I cannot move the mouse around.

Another method I tried to fix the issue was editing the FirstPersonController.cs script by making the m_MouseLook variable public and altering some components but that didn't work also. (For the same reason as disabling the script).

Any idea's or suggestions would be greatly appreciated.