CEC-3905 - car log level form debug mask disabled (#289)

src/components/Cars/Update/index.jsx

@@ -146,7 +146,7 @@ const MainForm = () => {
           max_mem_buffer_size: canbusEnabled ? parseInt(maxMemBufferSize) : 0,
           max_disk_buffer_size: canbusEnabled && dataLoggerEnabled ? parseInt(maxDiskBufferSize) : 0
         },
-        debug_mask: debugMaskEl.current.value
+        debug_mask: debugMaskEl.current?.value
       };
 
       const result = await updateVehicle(vin, formData, token);