add dependency for useEffect

src/Events.js

@@ -115,10 +115,12 @@ export default function Events() {
   const [events, setEvents] = useState(null)
 
   useEffect(async () => {
-    const res = await fetch(endpoint, fetch_options)
-    const result = await res.json()
-    setEvents(result)
-  }, [])
+    if (events === null) {
+      const res = await fetch(endpoint, fetch_options)
+      const result = await res.json()
+      setEvents(events)
+    }
+  }, [events])
 
   if (events === null) {
     return <p>Laster arrangement...</p>