I dont know why, but some of my pawns get this error while they are completing task:

Exception in JobDriver tick for pawn *Pawn Name* driver=JobDriver_ShootingRange_NonJoy (toilIndex=3)
System.NullReferenceException: Object reference not set to an instance of an object
at TrainingFacility.JobDriver_ShootingRange.WatchTickAction () [0x00291] in <dd505e6873794196b7d2136b71f0ec8a>:0
at TrainingFacility.JobDriver_ShootingRange+<>c__DisplayClass8_0.<GetToil_ShootAtTarget>b__0 () [0x00000] in <dd505e6873794196b7d2136b71f0ec8a>:0
at Verse.AI.JobDriver.DriverTick () [0x00163] in <3cca3e6203e64b109fd8ce21f7120d03>:0
UnityEngine.StackTraceUtility:ExtractStackTrace ()
(wrapper dynamic-method) Verse.Log:Verse.Log.Error_Patch2 (string)
Verse.AI.JobUtility:TryStartErrorRecoverJob (Verse.Pawn,string,System.Exception,Verse.AI.JobDriver)
Verse.AI.JobDriver:DriverTick ()
Verse.AI.Pawn_JobTracker:JobTrackerTick ()
Verse.Pawn:Tick ()
Verse.TickList:Tick ()
(wrapper dynamic-method) Verse.TickManager:Verse.TickManager.DoSingleTick_Patch3 (Verse.TickManager)
Verse.TickManager:TickManagerUpdate ()
(wrapper dynamic-method) Verse.Game:Verse.Game.UpdatePlay_Patch1 (Verse.Game)
Verse.Root_Play:Update ()