diff --git a/lbplanner/classes/helpers/plan_helper.php b/lbplanner/classes/helpers/plan_helper.php
index 76afb05f..aec2f61b 100644
--- a/lbplanner/classes/helpers/plan_helper.php
+++ b/lbplanner/classes/helpers/plan_helper.php
@@ -118,7 +118,7 @@ public static function get_access_type(int $userid, int $planid): int {
         if ($field === false) {
             return PLAN_ACCESS_TYPE::NONE;
         } else {
-            return PLAN_ACCESS_TYPE::from($field);
+            return PLAN_ACCESS_TYPE::from((int)$field);
         }
     }
 
diff --git a/lbplanner/classes/polyfill/Enum.php b/lbplanner/classes/polyfill/Enum.php
index dde1b238..0d9ec212 100644
--- a/lbplanner/classes/polyfill/Enum.php
+++ b/lbplanner/classes/polyfill/Enum.php
@@ -26,7 +26,6 @@
 namespace local_lbplanner\polyfill;
 
 use ReflectionClass;
-use ValueError;
 use local_lbplanner\polyfill\EnumCase;
 
 /**
@@ -38,7 +37,7 @@ class Enum {
      * @param mixed $value the value to be matched
      * @param bool $try whether to return null (true) or throw an error (false) if not found
      * @return ?EnumCase the matching enum case or null if not found and $try==true
-     * @throws ValueError if not found and $try==false
+     * @throws \moodle_exception if not found and $try==false
      */
     private static function find(mixed $value, bool $try): ?EnumCase {
         foreach (static::cases() as $case) {
@@ -50,7 +49,7 @@ private static function find(mixed $value, bool $try): ?EnumCase {
         if ($try) {
             return null;
         } else {
-            throw new ValueError("value {$value} cannot be represented as a value in enum ".static::class);
+            throw new \moodle_exception("value {$value} cannot be represented as a value in enum ".static::class);
         }
     }
     /**
diff --git a/lbplanner/services/plan/set_deadline.php b/lbplanner/services/plan/set_deadline.php
index a1d252af..71a612ce 100644
--- a/lbplanner/services/plan/set_deadline.php
+++ b/lbplanner/services/plan/set_deadline.php
@@ -87,10 +87,10 @@ public static function set_deadline(int $moduleid, int $deadlinestart, int $dead
             throw new \moodle_exception('Access denied');
         }
 
-        // If a deadline already exists.
-        if (!$DB->record_exists(plan_helper::DEADLINES_TABLE, ['moduleid' => $moduleid, 'planid' => $planid])) {
+        $deadline = $DB->get_record(plan_helper::DEADLINES_TABLE, ['moduleid' => $moduleid, 'planid' => $planid]);
+
+        if ($deadline !== false) {
             // Update the existing deadline.
-            $deadline = $DB->get_record(plan_helper::DEADLINES_TABLE, ['moduleid' => $moduleid, 'planid' => $planid]);
 
             $deadline->deadlinestart = $deadlinestart;
             $deadline->deadlineend = $deadlineend;