diff --git a/src/Plugin/FullcalendarViewProcessor/SmartDateProcessor.php b/src/Plugin/FullcalendarViewProcessor/SmartDateProcessor.php
index 20d8d4d..477c451 100644
--- a/src/Plugin/FullcalendarViewProcessor/SmartDateProcessor.php
+++ b/src/Plugin/FullcalendarViewProcessor/SmartDateProcessor.php
@@ -121,6 +121,9 @@ class SmartDateProcessor extends FullcalendarViewProcessorBase {
    *   Formatting options from the specified Smart Date Format.
    */
   private function updateEntry(array &$entry, array $row_data, array $format) {
+    if (!isset($row_data['value']) || !isset($row_data['end_value'])) {
+      return FALSE;
+    }
     $start = $row_data['value'];
     $end = $row_data['end_value'];
     if (empty($entry) || empty($start) || empty($end) || !ctype_digit($start) || !ctype_digit($end)) {