diff --git a/query-node/CHANGELOG.md b/query-node/CHANGELOG.md
index 81ae0820eb..fdcb3e3ed6 100644
--- a/query-node/CHANGELOG.md
+++ b/query-node/CHANGELOG.md
@@ -1,3 +1,7 @@
+### Unreleased
+
+- Fix mappings for `workingGroups_NewMissedRewardLevelReached` event to properly handle worker missing rewards updates
+
 ### 2.2.1
 
 - Bump deps @polkadot/api v10.7.1
diff --git a/query-node/mappings/src/workingGroups.ts b/query-node/mappings/src/workingGroups.ts
index 4f1b7524aa..b8ea3162cd 100644
--- a/query-node/mappings/src/workingGroups.ts
+++ b/query-node/mappings/src/workingGroups.ts
@@ -865,7 +865,7 @@ export async function workingGroups_NewMissedRewardLevelReached({
   await store.save<NewMissedRewardLevelReachedEvent>(newMissedRewardLevelReachedEvent)
 
   // Update worker
-  worker.missingRewardAmount = newMissedRewardAmountOpt.unwrapOr(undefined)
+  worker.missingRewardAmount = newMissedRewardAmountOpt.unwrapOr(new BN(0))
 
   await store.save<Worker>(worker)
 }