diff --git a/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.h b/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.h
index e91640bfd..886cda483 100644
--- a/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.h	
+++ b/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.h	
@@ -75,7 +75,7 @@ typedef void (^DSTransactionRequestRelayCompletionBlock)(DSTransaction *tx, DSPa
 
 - (DSBloomFilter *)transactionsBloomFilterForPeer:(DSPeer *)peer;
 
-- (void)publishTransaction:(DSTransaction *)transaction completion:(void (^)(NSError *error))completion;
+- (void)publishTransaction:(DSTransaction *)transaction completion:(void (^)(NSError * _Nullable error))completion;
 
 - (void)confirmPaymentRequest:(DSPaymentRequest *)paymentRequest usingUserBlockchainIdentity:(DSBlockchainIdentity *_Nullable)blockchainIdentity fromAccount:(DSAccount *)account acceptInternalAddress:(BOOL)acceptInternalAddress acceptReusingAddress:(BOOL)acceptReusingAddress addressIsFromPasteboard:(BOOL)addressIsFromPasteboard requiresSpendingAuthenticationPrompt:(BOOL)requiresSpendingConfirmationPrompt
     keepAuthenticatedIfErrorAfterAuthentication:(BOOL)keepAuthenticatedIfErrorAfterAuthentication
diff --git a/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.m b/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.m
index e572d05b4..f332f1a4b 100644
--- a/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.m	
+++ b/DashSync/shared/Models/Managers/Chain Managers/DSTransactionManager.m	
@@ -175,7 +175,7 @@ - (void)addUnconfirmedTransactionToPublishList:(DSTransaction *)transaction {
     }
 }
 
-- (void)publishTransaction:(DSTransaction *)transaction completion:(void (^)(NSError *error))completion {
+- (void)publishTransaction:(DSTransaction *)transaction completion:(void (^)(NSError * _Nullable error))completion {
 #if DEBUG
     DSLogPrivate(@"[DSTransactionManager] publish transaction %@ %@", transaction, transaction.toData);
 #else