My raycast randomly stops working.

Hello everyone.

I'm working on a mobile game where you have to control a traffic intersection. You have to 'swipe' on the cars to boost them and make them cross the intersection. All cars have a touchcollider onto which I cast a ray. The ray ignores all layers but the "touchinput" layer. This all works perfectly, but after a specific event the ray doesn't detect the collider anymore. This happens at random times, only after the specific event and only for a random amount of seconds. After the amount of seconds, it stars working again. I'm using this forum as a last resort because I've tried everything. I've logged and checked everything. The ray returns false and I can't figure out why.

 /// <summary>
     /// This method will execute the beginclick or touch logic
     /// depending on what the player did
     /// </summary>
     private void ExecuteBeginClickOrTouchLogic()
     {
         // Start the swipe timer
         _currentSwipeTime = TimeBetweenSwipe;
 
         // Save begin touch
         _firstPressPos = new Vector2(Input.mousePosition.x, Input.mousePosition.y);
 
         // Raycast down to see if you hit a vehicle and hold it
         Ray screenRay = Camera.main.ScreenPointToRay(_firstPressPos);
         RaycastHit rHit = new RaycastHit();
         if (Physics.Raycast(screenRay, out rHit, 1000.0f, VehicleLayer.value, QueryTriggerInteraction.Collide))
         {
             // If you clicked a vehicle, save the reference to its behaviour
             VehicleBehaviour vb = rHit.collider.GetComponentInParent<VehicleBehaviour>();
             print(Vector3.Distance(Camera.main.transform.position, vb.gameObject.transform.position));
 
             if (vb != null)
             {
                 _vehicleBehaviour = vb;
             }
             else // clean the reference to the previous behaviour
             {
                 _vehicleBehaviour = null;
             }
 
             // If you clicked a pedestrian, save the reference to its behaviour
             PedestrianBehaviour pb = rHit.collider.GetComponentInParent<PedestrianBehaviour>();
             if (pb != null && pb.IsCrossingOver == true)
             {
                 _pedestrianBehaviour = pb;
                 _pedestrianBehaviour.Drag();
             }
             else // clean the reference to the previous behaviour
             {
                 _pedestrianBehaviour = null;
             }
         }
         else // Otherwise clean up both
         {
             _vehicleBehaviour = null;
             _pedestrianBehaviour = null;
         }
     }

Does anyone have an idea?

Thanks in advance.