diff --git a/Modules/QuestieLearner.lua b/Modules/QuestieLearner.lua
index e262ab2..39ec5aa 100644
--- a/Modules/QuestieLearner.lua
+++ b/Modules/QuestieLearner.lua
@@ -3346,6 +3346,12 @@ function QuestieLearner:OnQuestComplete()
     local questId = GetQuestID and GetQuestID()
     if not questId or questId <= 0 then return end
 
+    _Learner.lastQuestComplete = {
+        id = questId,
+        ts = time(),
+        zoneId = GetZoneId(),
+    }
+
     -- Get current zone for quest giver spawn data
     local zoneId = GetZoneId()
 
@@ -3457,6 +3463,24 @@ local function ResolveAcceptedQuestId(firstArg, secondArg)
     return nil
 end
 
+local function ResolveTurnedInQuestId(rawQuestId)
+    if rawQuestId and type(rawQuestId) == "number" and rawQuestId > 0 then
+        if QuestieCompat.GetQuestLogIndexByID and QuestieCompat.GetQuestLogIndexByID(rawQuestId) then
+            return rawQuestId
+        end
+        if _Learner.lastQuestComplete and _Learner.lastQuestComplete.id == rawQuestId then
+            return rawQuestId
+        end
+    end
+
+    local last = _Learner.lastQuestComplete
+    if last and last.id and last.ts and (time() - last.ts) <= 10 then
+        return last.id
+    end
+
+    return nil
+end
+
 -- Fires when a quest is accepted.
 function QuestieLearner:OnQuestAccepted(firstArg, secondArg)
     Questie:Debug(Questie.DEBUG_INFO, "[QuestieLearner] OnQuestAccepted raw args: first=" .. tostring(firstArg) .. " second=" .. tostring(secondArg))
@@ -3607,7 +3631,7 @@ end
 function QuestieLearner:OnQuestTurnedIn(questId, xpReward, moneyReward)
     if not self:IsEnabled() then return end
     if not Questie.dbLearner.global.settings.learnQuests then return end
-    questId = tonumber(questId)
+    questId = ResolveTurnedInQuestId(tonumber(questId))
     if not questId or questId <= 0 then return end
 
     local data = {}
diff --git a/Tests/QuestieLearnerDataSourceMode_spec.lua b/Tests/QuestieLearnerDataSourceMode_spec.lua
index 60fd017..fd63a2d 100644
--- a/Tests/QuestieLearnerDataSourceMode_spec.lua
+++ b/Tests/QuestieLearnerDataSourceMode_spec.lua
@@ -270,6 +270,68 @@ describe("QuestieLearner quest accept resolution", function()
     end)
 end)
 
+describe("QuestieLearner quest turn-in resolution", function()
+    local QuestieLearner
+    local originalLearnQuest
+    local originalGetQuestID
+    local originalGetRewardText
+    local originalUnitGUID
+
+    before_each(function()
+        dofile("Tests/wow_api_mock.lua")
+
+        originalGetQuestID = _G.GetQuestID
+        originalGetRewardText = _G.GetRewardText
+        originalUnitGUID = _G.UnitGUID
+
+        Questie.dbLearner.global.settings.enabled = true
+        Questie.dbLearner.global.settings.dataSourceMode = "learner"
+
+        _G.GetQuestID = function()
+            return 4321
+        end
+        _G.GetRewardText = function()
+            return "Reward text"
+        end
+        _G.UnitGUID = function()
+            return nil
+        end
+
+        QuestieLearner = dofile("Modules/QuestieLearner.lua")
+        originalLearnQuest = QuestieLearner.LearnQuest
+    end)
+
+    after_each(function()
+        QuestieLearner.LearnQuest = originalLearnQuest
+        _G.GetQuestID = originalGetQuestID
+        _G.GetRewardText = originalGetRewardText
+        _G.UnitGUID = originalUnitGUID
+    end)
+
+    it("rejects malformed turn-in quest ids unless they resolve to a recent completion", function()
+        local capturedQuestId = nil
+        QuestieLearner.LearnQuest = function(self, questId, data)
+            capturedQuestId = questId
+        end
+
+        QuestieLearner:OnQuestTurnedIn(545915281, nil, nil)
+
+        assert.is_nil(capturedQuestId)
+    end)
+
+    it("uses the recent quest-complete cache when the raw turn-in quest id is malformed", function()
+        local capturedQuestId = nil
+        QuestieLearner.LearnQuest = function(self, questId, data)
+            capturedQuestId = questId
+        end
+
+        QuestieLearner:OnQuestComplete()
+        QuestieLearner:OnQuestTurnedIn(545915281, nil, nil)
+
+        assert.equals(4321, capturedQuestId)
+    end)
+end)
+
 describe("QuestieLearner GUID and loot learning", function()
     local QuestieLearner
     local originalGetNPC