diff --git a/.gitignore b/.gitignore
index a08302f..b726d58 100644
--- a/.gitignore
+++ b/.gitignore
@@ -46,5 +46,8 @@ development/node_modules/
 # Local History for Visual Studio Code
 .history/
 
+## vim
+.phpactor.json
+
 # macOS
 .DS_Store
diff --git a/classes/grading/grading_service.php b/classes/grading/grading_service.php
index 23a01f9..a058743 100644
--- a/classes/grading/grading_service.php
+++ b/classes/grading/grading_service.php
@@ -74,7 +74,7 @@ public static function get_line_item(int $courseid, int $cmid, string $resourcel
      *
      * @param int $courseid
      * @param int $cmid
-     * @param array $data array with required fields userId, scoreGiven, comment, timestamp
+     * @param array $data array with required field userId
      * @return bool Returns true if the grade information could be persisted.
      * @throws LtiException
      * @throws \coding_exception
@@ -91,14 +91,14 @@ public static function update_grade(int $courseid, int $cmid, array $data): bool
             throw new LtiException("Grade item for module CMID=$cmid (instance={$module->instance}) not found");
         }
 
-        // Validate that the required fields exist in $data.
-        if (!isset($data['userId']) || !isset($data['scoreGiven']) || !isset($data['timestamp'])) {
-            throw new LtiException("Missing required fields in the request body");
+        // Validate that the userId exist in $data.
+        if (!isset($data['userId'])) {
+            throw new LtiException("Missing userId in the request body");
         }
 
         // Receive a score for the line item via JSON request body.
         $userid = $data['userId'];
-        $scoregiven = isset($data['scoreGiven']) ? max(0, min(floatval($data['scoreGiven']), $gradeitem->grademax)) : null;
+        $scoregiven = isset($data['scoreGiven']) ? floatval($data['scoreGiven']) : null;
         $comment = $data['comment'] ?? '';
         $timestamp = isset($data['timestamp']) ? strtotime($data['timestamp']) : time();
 
diff --git a/lib.php b/lib.php
index c996760..75fb9e9 100644
--- a/lib.php
+++ b/lib.php
@@ -213,7 +213,7 @@ function kialo_grade_item_update(stdClass $kialo, ?stdClass $grades = null): int
         'idnumber' => $kialo->cmidnumber ?? '',
     ];
 
-    if ($kialo->grade > 0) {
+    if ($kialo->grade >= 0) {
         $params['gradetype'] = GRADE_TYPE_VALUE;
         $params['grademax']  = $kialo->grade;
         $params['grademin']  = 0;