diff --git a/WordPress/Classes/Services/AccountService.h b/WordPress/Classes/Services/AccountService.h
index d1ea256c9847..8a793f6f9b86 100644
--- a/WordPress/Classes/Services/AccountService.h
+++ b/WordPress/Classes/Services/AccountService.h
@@ -85,7 +85,7 @@ extern NSNotificationName const WPAccountEmailAndDefaultBlogUpdatedNotification;
  @param failure A failure block.
  */
 - (void)createOrUpdateAccountWithAuthToken:(NSString *)authToken
-                                   success:(void (^)(WPAccount * _Nonnull))success
+                                   success:(void (^)(WPAccount * _Nullable))success
                                    failure:(void (^)(NSError * _Nonnull))failure;
 
 - (NSManagedObjectID *)createOrUpdateAccountWithUserDetails:(RemoteUser *)remoteUser authToken:(NSString *)authToken;
diff --git a/WordPress/Classes/Services/AccountService.m b/WordPress/Classes/Services/AccountService.m
index 58f0c4887eec..8a669e174e30 100644
--- a/WordPress/Classes/Services/AccountService.m
+++ b/WordPress/Classes/Services/AccountService.m
@@ -180,7 +180,7 @@ - (WPAccount *)findDefaultAccountCandidateFromAccounts:(NSArray *)allAccounts
 }
 
 - (void)createOrUpdateAccountWithAuthToken:(NSString *)authToken
-                                   success:(void (^)(WPAccount * _Nonnull))success
+                                   success:(void (^)(WPAccount * _Nullable))success
                                    failure:(void (^)(NSError * _Nonnull))failure
 {
     WordPressComRestApi *api = [WordPressComRestApi defaultApiWithOAuthToken:authToken userAgent:[WPUserAgent wordPressUserAgent] localeKey:[WordPressComRestApi LocaleKeyDefault]];
diff --git a/WordPress/Classes/Services/WordPressComSyncService.swift b/WordPress/Classes/Services/WordPressComSyncService.swift
index 802f7a1c0b18..3aaeca35024b 100644
--- a/WordPress/Classes/Services/WordPressComSyncService.swift
+++ b/WordPress/Classes/Services/WordPressComSyncService.swift
@@ -24,6 +24,10 @@ class WordPressComSyncService {
     func syncWPCom(authToken: String, isJetpackLogin: Bool, onSuccess: @escaping (WPAccount) -> Void, onFailure: @escaping (Error) -> Void) {
         let accountService = AccountService(coreDataStack: coreDataStack)
         accountService.createOrUpdateAccount(withAuthToken: authToken, success: { account in
+            guard let account else {
+                onFailure(URLError(.unknown))
+                return
+            }
             self.syncOrAssociateBlogs(account: account, isJetpackLogin: isJetpackLogin, onSuccess: onSuccess, onFailure: onFailure)
         }, failure: { error in
             onFailure(error)