Can't find the original issue in out database but i did find the imgur link [https://imgur.com/nracReJ] 
{code:java}
Failed to define FlowFunctionUnit#a4f17...:<br>System.ArgumentException: Duplicate input for 'target' in Ludiq.Bolt.FlowFunctionUnit.<br> at Ludiq.Bolt.UnitDefinitionUtility.EnsureUniqueInput (Ludiq.Bolt.IUnit unit, System.String key) [0x00031] in C:\GameDev\alpha7_3\Assets\Ludiq\Bolt.Flow\Runtime\Units\UnitDefinitionUtility.cs:12 <br> at Ludiq.Bolt.UnitDefinitionUtility.DefineValueInput (Ludiq.Bolt.IUnit unit, Ludiq.Bolt.ValueInputDefinition definition) [0x00012] in C:\GameDev\alpha7_3\Assets\Ludiq\Bolt.Flow\Runtime\Units\UnitDefinitionUtility.cs:97 <br> at Ludiq.Bolt.Unit`1[TFlowGraph].ValueInput (Ludiq.Bolt.ValueInputDefinition definition) [0x00001] in C:\GameDev\alpha7_3\Assets\Ludiq\Bolt.Flow\Runtime\Units\Unit.cs:402 <br> at Ludiq.Bolt.FlowFunctionUnit.Definition () [0x0009f] in C:\GameDev\alpha7_3\Assets\Ludiq\Bolt.Flow\Runtime\Units\Architecture\FlowFunctionUnit.cs:56 <br> at Ludiq.Bolt.Unit`1[TFlowGraph].Define () [0x00041] in C:\GameDev\alpha7_3\Assets\Ludiq\Bolt.Flow\Runtime\Units\Unit.cs:188 <br>UnityEngine.Debug:LogWarning(Object)<br>Ludiq.Bolt.Unit`1:Define() (at Assets/Ludiq/Bolt.Flow/Runtime/Units/Unit.cs:204)<br>Ludiq.Bolt.Unit`1:AfterAdd(FlowGraph) (at Assets/Ludiq/Bolt.Flow/Runtime/Units/Unit.cs:96)<br>Ludiq.Bolt.MemberDefinitionUnit`2:AfterAdd(FlowGraph) (at Assets/Ludiq/Bolt.Flow/Runtime/Units/Architecture/MemberDefinitionUnit.cs:93)<br>Ludiq.Bolt.GraphElement`1:Ludiq.INotifiedCollectionChild.AfterAdd(IGraph) (at Assets/Ludiq/Bolt.Core/Runtime/Graphs/GraphElement.cs:48)<br>Ludiq.ParentCollection`3:AfterAdd(IUnit) (at Assets/Ludiq/Ludiq.Core/Runtime/Collections/ParentCollection.cs:302)<br>Ludiq.ParentCollection`3:InsertItem(Int32, IUnit) (at Assets/Ludiq/Ludiq.Core/Runtime/Collections/ParentCollection.cs:91)<br>System.Collections.ObjectModel.Collection`1:Add(IUnit)<br>Ludiq.Bolt.FlowCanvas:AddUnit(IUnit, Vector2) (at Assets/Ludiq/Bolt.Flow/Editor/FlowCanvas.cs:218)<br>Ludiq.Bolt.FlowCanvas:PerformDragAndDrop() (at Assets/Ludiq/Bolt.Flow/Editor/FlowCanvas.cs:479)<br>Ludiq.Bolt.Canvas:HandleDragAndDrop() (at Assets/Ludiq/Bolt.Core/Editor/Canvases/Canvas.cs:2097)<br>Ludiq.Bolt.Canvas:HandleLowPriorityInput() (at Assets/Ludiq/Bolt.Core/Editor/Canvases/Canvas.cs:375)<br>Ludiq.Bolt.FlowCanvas:HandleLowPriorityInput() (at Assets/Ludiq/Bolt.Flow/Editor/FlowCanvas.cs:135)<br>Ludiq.Bolt.Canvas:OnGUI() (at Assets/Ludiq/Bolt.Core/Editor/Canvases/Canvas.cs:312)<br>Ludiq.Bolt.GraphWindow:_OnGUI() (at Assets/Ludiq/Bolt.Core/Editor/Windows/GraphWindow.cs:667)<br>Ludiq.LudiqEditorWindow:OnGUI() (at Assets/Ludiq/Ludiq.Core/Editor/Windows/LudiqEditorWindow.cs:136)<br>UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr) (at C:/buildslave/unity/build/Modules/IMGUI/GUIUtility.cs:179){code}