diff --git a/components/scheduler/src/main/java/org/cardanofoundation/ledgersync/scheduler/service/impl/PoolOfflineDataStoringServiceImpl.java b/components/scheduler/src/main/java/org/cardanofoundation/ledgersync/scheduler/service/impl/PoolOfflineDataStoringServiceImpl.java
index 34806de1..9b898c5f 100644
--- a/components/scheduler/src/main/java/org/cardanofoundation/ledgersync/scheduler/service/impl/PoolOfflineDataStoringServiceImpl.java
+++ b/components/scheduler/src/main/java/org/cardanofoundation/ledgersync/scheduler/service/impl/PoolOfflineDataStoringServiceImpl.java
@@ -61,7 +61,6 @@ public PoolOfflineDataStoringServiceImpl(
     public void saveSuccessPoolOfflineData(List<PoolData> successPools) {
         long startTime = System.currentTimeMillis();
         log.info("Start saving success pool offline data");
-        List<PoolOfflineData> poolOfflineDataNeedSave = new ArrayList<>();
 
         List<Long> poolIds = successPools.stream().map(PoolData::getPoolId).toList();
         List<Long> poolMetadataRefIds = successPools.stream().map(PoolData::getMetadataRefId).toList();
@@ -84,7 +83,7 @@ public void saveSuccessPoolOfflineData(List<PoolData> successPools) {
                 .stream()
                 .collect(Collectors.toMap(PoolOfflineData::getPoolId, Function.identity()));
 
-        poolDataMap.entrySet().parallelStream().forEach(poolDataEntry -> {
+        List<PoolOfflineData> poolOfflineDataNeedSave = poolDataMap.entrySet().parallelStream().map(poolDataEntry -> {
             Long poolId = poolDataEntry.getKey();
             PoolData poolData = poolDataEntry.getValue();
             PoolHash poolHash = poolHashMap.get(poolId);
@@ -96,9 +95,10 @@ public void saveSuccessPoolOfflineData(List<PoolData> successPools) {
                 if (poolOfflineDataSourceMap.containsKey(poolId)) {
                     poolOfflineData.setId(poolOfflineDataSourceMap.get(poolId).getId());
                 }
-                poolOfflineDataNeedSave.add(poolOfflineData);
             }
-        });
+
+            return poolOfflineData;
+        }).filter(Objects::nonNull).collect(Collectors.toList());
 
         poolOfflineDataRepository.saveAll(poolOfflineDataNeedSave);
         log.info("Saved success pool offline data, count: {}, time taken: {} ms",
@@ -111,7 +111,6 @@ public void saveFailOfflineData(List<PoolData> failedPools) {
         long startTime = System.currentTimeMillis();
 
         log.info("Start saving fail pool offline data");
-        List<PoolOfflineFetchError> poolOfflineFetchErrorsNeedSave = new ArrayList<>();
 
         List<Long> poolIds = failedPools.stream().map(PoolData::getPoolId).toList();
         List<Long> poolMetadataRefIds = failedPools.stream().map(PoolData::getMetadataRefId).toList();
@@ -130,7 +129,8 @@ public void saveFailOfflineData(List<PoolData> failedPools) {
                 .stream()
                 .collect(Collectors.toMap(PoolMetadataRef::getId, Function.identity()));
 
-        poolDataMap.entrySet().parallelStream().forEach(poolDataEntry -> {
+        List<PoolOfflineFetchError> poolOfflineFetchErrorsNeedSave =
+                poolDataMap.entrySet().parallelStream().map(poolDataEntry -> {
             Long poolId = poolDataEntry.getKey();
             PoolData poolData = poolDataEntry.getValue();
             PoolHash poolHash = poolHashMap.get(poolId);
@@ -153,8 +153,9 @@ public void saveFailOfflineData(List<PoolData> failedPools) {
                         .fetchTime(Timestamp.valueOf(LocalDateTime.now(ZoneOffset.UTC)))
                         .build();
             }
-            poolOfflineFetchErrorsNeedSave.add(poolOfflineFetchError);
-        });
+
+            return poolOfflineFetchError;
+        }).collect(Collectors.toList());
 
         poolOfflineFetchErrorRepository.saveAll(poolOfflineFetchErrorsNeedSave);
         log.info("Saved success fail pool offline data, count: {}, time taken: {} ms",