diff --git a/htdocs/projet/class/task.class.php b/htdocs/projet/class/task.class.php
index 83b9b1e55a8ef..d2a4cc606aa73 100644
--- a/htdocs/projet/class/task.class.php
+++ b/htdocs/projet/class/task.class.php
@@ -6,7 +6,7 @@
  * Copyright (C) 2020       Juanjo Menent		<jmenent@2byte.es>
  * Copyright (C) 2022       Charlene Benke		<charlene@patas-monkey.com>
  * Copyright (C) 2023      	Gauthier VERDOL     <gauthier.verdol@atm-consulting.fr>
- * Copyright (C) 2024		MDW							<mdeweerd@users.noreply.github.com>
+ * Copyright (C) 2024-2025	MDW							<mdeweerd@users.noreply.github.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -1417,9 +1417,9 @@ public function mergeTimeSpentTask($origin_id, $dest_id)
 	/**
 	 *  Add time spent
 	 *
-	 *  @param	User	$user           User object
-	 *  @param  int		$notrigger	    0=launch triggers after, 1=disable triggers
-	 *  @return	int                     Return integer <=0 if KO, >0 if OK
+	 *  @param	User		$user		User object
+	 *  @param	int<0,1>	$notrigger	0=launch triggers after, 1=disable triggers
+	 *  @return	int				Return integer <=0 if KO, >0 if OK
 	 */
 	public function addTimeSpent($user, $notrigger = 0)
 	{
diff --git a/htdocs/projet/tasks/time.php b/htdocs/projet/tasks/time.php
index 4f7541724fc46..6afdc5bc7c323 100644
--- a/htdocs/projet/tasks/time.php
+++ b/htdocs/projet/tasks/time.php
@@ -7,7 +7,7 @@
  * Copyright (C) 2018       Frédéric France         <frederic.france@netlogic.fr>
  * Copyright (C) 2019-2021  Christophe Battarel		<christophe@altairis.fr>
  * Copyright (C) 2023      	Gauthier VERDOL       	<gauthier.verdol@atm-consulting.fr>
- * Copyright (C) 2024		MDW						<mdeweerd@users.noreply.github.com>
+ * Copyright (C) 2024-2025	MDW						<mdeweerd@users.noreply.github.com>
  * Copyright (C) 2024		Vincent de Grandpré		<vincent@de-grandpre.quebec>
  * Copyright (C) 2024		Solution Libre SAS		<contact@solution-libre.fr>
  *
@@ -270,6 +270,7 @@
 
 if (($action == 'updateline' || $action == 'updatesplitline') && !$cancel && $user->hasRight('projet', 'lire')) {
 	$error = 0;
+	$db->begin();
 
 	if (!GETPOST("new_durationhour") && !GETPOST("new_durationmin")) {
 		setEventMessages($langs->trans('ErrorFieldRequired', $langs->transnoentitiesnoconv("Duration")), null, 'errors');
@@ -300,10 +301,21 @@
 			} else {
 				$object->timespent_date = dol_mktime(12, 0, 0, GETPOST("timelinemonth"), GETPOST("timelineday"), GETPOST("timelineyear"));
 			}
-			$object->timespent_fk_user = GETPOSTINT("userid_line");
-			$object->timespent_fk_product = GETPOSTINT("fk_product");
-			$object->timespent_invoiceid = GETPOSTINT("invoiceid");
-			$object->timespent_invoicelineid = GETPOSTINT("invoicelineid");
+
+			// Use fields from existing record or from post (if provided)
+			if (GETPOST("userid_line") != '') {
+				$object->timespent_fk_user = GETPOSTINT("userid_line");
+			}
+			if (GETPOST("fk_product") != '') {
+				$object->timespent_fk_product = GETPOSTINT("fk_product");
+			}
+			if (GETPOST("invoiceid") != '') {
+				$object->timespent_invoiceid = GETPOSTINT("invoiceid");
+			}
+			if (GETPOST("invoicelineid") != '') {
+				$object->timespent_invoicelineid = GETPOSTINT("invoicelineid");
+			}
+
 
 			$result = 0;
 			if (in_array($object->timespent_fk_user, $childids) || $user->hasRight('projet', 'all', 'creer')) {
@@ -349,6 +361,11 @@
 	} else {
 		$action = '';
 	}
+	if ($error == 0) {
+		$db->commit();
+	} else {
+		$db->rollback();
+	}
 }
 
 if ($action == 'confirm_deleteline' && $confirm == "yes" && ($user->hasRight('projet', 'time') || $user->hasRight('projet', 'all', 'creer'))) {