Can't turn in repulsive device

[gewd]

Attempting to turn in the repulsive device to Nacham results in “Here. Take It” dialogue choice missing.

https://wiki.cavesofqud.com/wiki/Nacham/Conversations#ConfirmRepairNacham

I traded for the repulsive device from the ooze instead of killing it. I did not do the optional objective “Speak with the Watchers”.

Version: 2.0.206.32

ERROR - Error adding Choice by ID RepairNachamChoice :System.NullReferenceException: Object reference not set to an instance of an object
  at XRL.World.Conversations.ConversationDelegates.RemoveItem (XRL.World.Conversations.DelegateContext Context) [0x00005] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.ConversationDelegates+<>c__DisplayClass13_0.<LoadDelegates>b__0 (XRL.World.Conversations.IConversationElement e, System.String x) [0x00012] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.IConversationElement.LoadAttributes (System.Collections.Generic.Dictionary`2[TKey,TValue] Attributes) [0x000cd] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.IConversationElement.Load (XRL.World.Conversations.ConversationXMLBlueprint Blueprint) [0x0000c] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.IConversationElement.Create[T] (XRL.World.Conversations.ConversationXMLBlueprint Blueprint) [0x00005] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.IConversationElement.LoadChild (XRL.World.Conversations.ConversationXMLBlueprint Blueprint) [0x0007a] in <55bc698050794051ad78b51df487fd82>:0 
  at XRL.World.Conversations.IConversationElement.Load (XRL.World.Conversations.ConversationXMLBlueprint Blueprint) [0x0003e] in <55bc698050794051ad78b51df487fd82>:0 

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