Hauler Bot (Tier 4) threw exception in WorkGiver HaulGeneral: System.NullReferenceException: Object reference not set to an instance of an object
  at RimWorld.StoreUtility.TryFindBestBetterStoreCellFor (Verse.Thing t, Verse.Pawn carrier, Verse.Map map, StoragePriority currentPriority, RimWorld.Faction faction, Verse.IntVec3& foundCell, Boolean needAccurateResult) [0x00000] in <filename unknown>:0
  at Verse.AI.HaulAIUtility.HaulToStorageJob (Verse.Pawn p, Verse.Thing t) [0x00000] in <filename unknown>:0
  at RimWorld.WorkGiver_HaulGeneral.JobOnThing (Verse.Pawn pawn, Verse.Thing t, Boolean forced) [0x00000] in <filename unknown>:0
  at RimWorld.WorkGiver_Scanner.HasJobOnThing (Verse.Pawn pawn, Verse.Thing t, Boolean forced) [0x00000] in <filename unknown>:0
  at AIRobot.X2_JobGiver_Work+<>c__DisplayClass1_1.<TryIssueJobPackage>b__0 (Verse.Thing t) [0x00000] in <filename unknown>:0
  at Verse.GenClosest+<ClosestThingReachable>c__AnonStorey0.<>m__0 (Verse.Thing t) [0x00000] in <filename unknown>:0
  at Verse.GenClosest.ClosestThing_Global (IntVec3 center, IEnumerable searchSet, Single maxDistance, System.Predicate`1 validator, System.Func`2 priorityGetter) [0x00000] in <filename unknown>:0
  at Verse.GenClosest.ClosestThingReachable (IntVec3 root, Verse.Map map, ThingRequest thingReq, PathEndMode peMode, TraverseParms traverseParams, Single maxDistance, System.Predicate`1 validator, IEnumerable`1 customGlobalSearchSet, Int32 searchRegionsMin, Int32 searchRegionsMax, Boolean forceGlobalSearch, RegionType traversableRegionTypes, Boolean ignoreEntirelyForbiddenRegions) [0x00000] in <filename unknown>:0
  at AIRobot.X2_JobGiver_Work.TryIssueJobPackage (Verse.Pawn pawn, JobIssueParams jobParams) [0x00000] in <filename unknown>:0
Verse.Log:Error(String)
AIRobot.X2_JobGiver_Work:TryIssueJobPackage(Pawn, JobIssueParams)
Verse.AI.ThinkNode_PrioritySorter:TryIssueJobPackage(Pawn, JobIssueParams)
Verse.AI.ThinkNode_Priority:TryIssueJobPackage(Pawn, JobIssueParams)
Verse.AI.ThinkNode_Conditional:TryIssueJobPackage(Pawn, JobIssueParams)
Verse.AI.ThinkNode_Priority:TryIssueJobPackage(Pawn, JobIssueParams)
Verse.AI.Pawn_JobTracker:DetermineNextJob(ThinkTreeDef&)
Verse.AI.Pawn_JobTracker:TryFindAndStartJob()
Verse.AI.Pawn_JobTracker:EndCurrentJob(JobCondition, Boolean)
Verse.AI.Pawn_JobTracker:JobTrackerTick()
Verse.Pawn:Tick()
AIRobot.X2_AIRobot:Tick()
Verse.TickList:Tick()
Verse.TickManager:DoSingleTick()
Verse.TickManager:TickManagerUpdate()
Verse.Game:UpdatePlay()
Verse.Root_Play:Update()