diff --git a/components/MonitorDetail.tsx b/components/MonitorDetail.tsx
index c2bb67f..0ff35bf 100644
--- a/components/MonitorDetail.tsx
+++ b/components/MonitorDetail.tsx
@@ -29,7 +29,7 @@ export default function MonitorDetail({
     )
 
   let statusIcon =
-    state.incident[monitor.id].slice(-1)[0].end === undefined ? (
+    state.incident[monitor.id].slice(-1)[0].end === null ? (
       <IconAlertCircle
         style={{ width: '1.25em', height: '1.25em', color: '#b91c1c', marginRight: '3px' }}
       />
diff --git a/components/MonitorList.tsx b/components/MonitorList.tsx
index 6444d5c..ab14eb2 100644
--- a/components/MonitorList.tsx
+++ b/components/MonitorList.tsx
@@ -12,7 +12,7 @@ function countDownCount(state: MonitorState, ids: string[]) {
       continue
     }
 
-    if (state.incident[id].slice(-1)[0].end === undefined) {
+    if (state.incident[id].slice(-1)[0].end === null) {
       downCount++
     }
   }