diff --git a/includes/ICS/Import.php b/includes/ICS/Import.php
index 1c3db637..9eff26f4 100644
--- a/includes/ICS/Import.php
+++ b/includes/ICS/Import.php
@@ -16,12 +16,13 @@ class Import
     /**
      * getEvents
      *
-     * @param string $url
+     * @param integer $feedID
      * @param boolean $cache
+     * @param integer $pastDays
      * @param integer $limitDays
      * @return mixed
      */
-    public static function getEvents(string $feedID, bool $cache = true, int $pastDays = 365, int $limitDays = 365)
+    public static function getEvents(int $feedID, bool $cache = true, int $pastDays = 365, int $limitDays = 365)
     {
         $pastDays = abs($pastDays);
         $limitDays = abs($limitDays);
@@ -46,6 +47,7 @@ public static function getEvents(string $feedID, bool $cache = true, int $pastDa
 
         // Fix URL protocol
         $url = get_post_meta($feedID, CalendarFeed::FEED_URL, true);
+        $url = $url ?: '';
         if (strpos($url, 'webcal://') === 0) {
             $url = str_replace('webcal://', 'https://', $url);
         }
diff --git a/rrze-calendar.php b/rrze-calendar.php
index c5afc94f..f726eb66 100644
--- a/rrze-calendar.php
+++ b/rrze-calendar.php
@@ -4,7 +4,7 @@
 Plugin Name:     RRZE Calendar
 Plugin URI:      https://github.com/RRZE-Webteam/rrze-calendar
 Description:     Import and output of FAU public events.
-Version:         2.0.10
+Version:         2.0.11
 Author:          RRZE Webteam
 Author URI:      https://blogs.fau.de/webworking/
 License:         GNU General Public License v3.0
@@ -21,8 +21,8 @@
 use RRZE\Calendar\CPT\CalendarFeed;
 use RRZE\WP\Plugin;
 
-const RRZE_PHP_VERSION = '8.0';
-const RRZE_WP_VERSION = '6.3';
+const RRZE_PHP_VERSION = '8.1';
+const RRZE_WP_VERSION = '6.4';
 
 // Autoloader
 require_once 'vendor/autoload.php';