diff --git a/src/module/cytoscapeMap.js b/src/module/cytoscapeMap.js
index e8af4e0..4be85b9 100644
--- a/src/module/cytoscapeMap.js
+++ b/src/module/cytoscapeMap.js
@@ -281,7 +281,7 @@ export default function cytoscapeMap(mapData, dataLayerType, dataLayerOption, cu
     if (node.data("label").length > 10) tip.show();
   });
   cy.on('mouseout', 'node', function (event) {
-    tip.hide();
+    tip?.hide();
   });
 
   // here we remember and recall positions