diff --git a/imports/ui/Overview.jsx b/imports/ui/Overview.jsx
index 020ace1..d7c03a9 100644
--- a/imports/ui/Overview.jsx
+++ b/imports/ui/Overview.jsx
@@ -73,7 +73,7 @@ export default function Overview() {
                         </Form>
                     </Col>
                     <Col>
-                        <h6>active device: {ConfiguredDevicesCollection.findOne({deviceId: activeDevice.deviceId}).alias}</h6>
+                        <h6>active device: {ConfiguredDevicesCollection.findOne({deviceId: activeDevice.deviceId}) === undefined ? "No device selected" : ConfiguredDevicesCollection.findOne({deviceId: activeDevice.deviceId}).alias}</h6>
                     </Col>
                 </Row>
 
diff --git a/imports/ui/SensorCardDeck.jsx b/imports/ui/SensorCardDeck.jsx
index 1c21dd4..7dabded 100644
--- a/imports/ui/SensorCardDeck.jsx
+++ b/imports/ui/SensorCardDeck.jsx
@@ -14,19 +14,32 @@ export default function SensorCardDeck() {
     });
 
     const sensorData = useTracker(() => {
-        return SensorDataCollection.find({ device_id: deviceId.deviceId }, { sort: { timestamp: -1 }, limit: 1 }).fetch();
+        if (deviceId === null || deviceId === undefined) {
+            return undefined;
+        } else {
+            return SensorDataCollection.find({device_id: deviceId.deviceId}, {sort: {timestamp: -1}, limit: 1}).fetch();
+        }
     });
 
     const plantType = useTracker(() => {
-        return ConfiguredDevicesCollection.findOne({ deviceId: deviceId.deviceId }).type;
+        if (deviceId === null || deviceId === undefined) {
+            return undefined;
+        } else {
+            return ConfiguredDevicesCollection.findOne({deviceId: deviceId.deviceId});
+        }
     });
 
     const plantTypeData = useTracker(() => {
-        return PlantTypesCollection.findOne({ plantType: plantType });
+        if (plantType === null || plantType === undefined) {
+            return undefined;
+        } else {
+            return PlantTypesCollection.findOne({plantType: plantType.type});
+        }
     });
 
+    console.log("Sens" + sensorData, plantType, plantTypeData, deviceId);
 
-    if (sensorData.length <= 0) {
+    if (sensorData.length <= 0 || plantType === undefined || deviceId === undefined || plantTypeData === undefined) {
         return (
             <CardDeck>
                 <Card>