diff --git a/Example/CoreData/SyncKitCoreDataExample/SyncKitCoreDataExampleTests/CloudKitSynchronizerTests.swift b/Example/CoreData/SyncKitCoreDataExample/SyncKitCoreDataExampleTests/CloudKitSynchronizerTests.swift
index 1604ad29..63ce3b96 100644
--- a/Example/CoreData/SyncKitCoreDataExample/SyncKitCoreDataExampleTests/CloudKitSynchronizerTests.swift
+++ b/Example/CoreData/SyncKitCoreDataExample/SyncKitCoreDataExampleTests/CloudKitSynchronizerTests.swift
@@ -240,11 +240,12 @@ class CloudKitSynchronizerTests: XCTestCase {
     func testSynchronize_limitExceededErrorInPartialError_decreasesBatchSizeAndEndsWithError() {
         let expectation = self.expectation(description: "sync finished")
         let batchSize = synchronizer.batchSize
+        let innerError = NSError(domain: CKErrorDomain,
+                                 code: CKError.limitExceeded.rawValue,
+                                 userInfo: nil)
         let error = NSError(domain: CKErrorDomain,
                             code: CKError.partialFailure.rawValue,
-                            userInfo: [CKPartialErrorsByItemIDKey: ["itemId": NSError(domain: CKErrorDomain,
-                                                                                      code: CKError.limitExceeded.rawValue,
-                                                                                      userInfo: nil)]])
+                            userInfo: [CKPartialErrorsByItemIDKey: [CKRecord.ID(recordName: "itemID", zoneID: recordZoneID): innerError]])
         mockDatabase.uploadError = error
         let object = QSObject(identifier: "1", number: 1)
         mockAdapter.objects = [object]
diff --git a/SyncKit/Classes/QSSynchronizer/CloudKitSynchronizer+Sync.swift b/SyncKit/Classes/QSSynchronizer/CloudKitSynchronizer+Sync.swift
index 6d7ec813..a1f89dc7 100644
--- a/SyncKit/Classes/QSSynchronizer/CloudKitSynchronizer+Sync.swift
+++ b/SyncKit/Classes/QSSynchronizer/CloudKitSynchronizer+Sync.swift
@@ -103,7 +103,7 @@ extension CloudKitSynchronizer {
     func isServerRecordChangedError(_ error: NSError) -> Bool {
         
         if error.code == CKError.partialFailure.rawValue,
-            let errorsByItemID = error.userInfo[CKPartialErrorsByItemIDKey] as? [String: NSError],
+            let errorsByItemID = error.userInfo[CKPartialErrorsByItemIDKey] as? [CKRecord.ID: NSError],
             errorsByItemID.values.contains(where: { (error) -> Bool in
                 return error.code == CKError.serverRecordChanged.rawValue
             }) {
@@ -126,7 +126,7 @@ extension CloudKitSynchronizer {
     func isLimitExceededError(_ error: NSError) -> Bool {
         
         if error.code == CKError.partialFailure.rawValue,
-            let errorsByItemID = error.userInfo[CKPartialErrorsByItemIDKey] as? [String: NSError],
+            let errorsByItemID = error.userInfo[CKPartialErrorsByItemIDKey] as? [CKRecord.ID: NSError],
             errorsByItemID.values.contains(where: { (error) -> Bool in
                 return error.code == CKError.limitExceeded.rawValue
             }) {