diff --git a/action/protocol/staking/handlers.go b/action/protocol/staking/handlers.go
index 9b171d66cb..8329b2149a 100644
--- a/action/protocol/staking/handlers.go
+++ b/action/protocol/staking/handlers.go
@@ -699,12 +699,11 @@ func (p *Protocol) handleCandidateRegister(ctx context.Context, act *action.Cand
 			}
 		}
 		candID = id
-	}
-	c = csm.GetByIdentifier(candID)
-	if c != nil {
-		return log, nil, &handleError{
-			err:           ErrInvalidOwner,
-			failureStatus: iotextypes.ReceiptStatus_ErrCandidateAlreadyExist,
+		if csm.GetByIdentifier(candID) != nil {
+			return log, nil, &handleError{
+				err:           ErrInvalidOwner,
+				failureStatus: iotextypes.ReceiptStatus_ErrCandidateAlreadyExist,
+			}
 		}
 	}
 	// cannot collide with existing name