diff --git a/dot/sync/message.go b/dot/sync/message.go
index 7baececb5e..b896ace9ce 100644
--- a/dot/sync/message.go
+++ b/dot/sync/message.go
@@ -231,8 +231,8 @@ func (s *Service) checkOrGetDescendantHash(ancestor common.Hash,
 		// if descendant number is lower than ancestor number, this is an error
 		if header.Number > descendantNumber {
 			return common.Hash{},
-				fmt.Errorf("invalid request, descendant number %d is higher than ancestor %d",
-					header.Number, descendantNumber)
+				fmt.Errorf("invalid request, descendant number %d is lower than ancestor %d",
+					descendantNumber, header.Number)
 		}
 
 		// check if provided start hash is descendant of provided descendant hash
diff --git a/dot/sync/message_test.go b/dot/sync/message_test.go
index 5853aa5e8a..8abfd1923f 100644
--- a/dot/sync/message_test.go
+++ b/dot/sync/message_test.go
@@ -256,7 +256,7 @@ func TestService_checkOrGetDescendantHash(t *testing.T) {
 			},
 			args:          args{ancestor: common.Hash{2}, descendant: &common.Hash{1, 2}, descendantNumber: 1},
 			want:          common.Hash{},
-			expectedError: errors.New("invalid request, descendant number 2 is higher than ancestor 1"),
+			expectedError: errors.New("invalid request, descendant number 1 is lower than ancestor 2"),
 		},
 	}
 	for _, tt := range tests {