diff --git a/project/src/controllers/GameController.ts b/project/src/controllers/GameController.ts
index e3172ec3..eb9229bb 100644
--- a/project/src/controllers/GameController.ts
+++ b/project/src/controllers/GameController.ts
@@ -651,7 +651,7 @@ export class GameController
                 if (!traderAssorts.loyal_level_items[assortKey])
                 {
                     // reverse lookup of enum key by value 
-                    this.logger.debug(this.localisationService.getText("assort-missing_quest_assort_unlock", {traderName: Object.keys(Traders)[Object.values(Traders).indexOf(traderId)], questName: quests[questKey].QuestName}));
+                    this.logger.debug(this.localisationService.getText("assort-missing_quest_assort_unlock", {traderName: Object.keys(Traders)[Object.values(Traders).indexOf(traderId)], questName: quests[questKey]?.QuestName ?? "UNKNOWN"}));
                 }
             }
         }