diff --git a/source/pathfinding/navigation_mesh.cpp b/source/pathfinding/navigation_mesh.cpp
index d468590..0376425 100644
--- a/source/pathfinding/navigation_mesh.cpp
+++ b/source/pathfinding/navigation_mesh.cpp
@@ -32,7 +32,8 @@ namespace omath::pathfinding
 
     void NavigationMesh::set_event(const Vector3<float>& vertex, std::string event_id)
     {
-        m_vertex_events[vertex] = std::move(event_id);
+        if (m_vertex_map.contains(vertex))
+            m_vertex_events[vertex] = std::move(event_id);
     }
 
     void NavigationMesh::clear_event(const Vector3<float>& vertex)