diff --git a/lang/en/message.php b/lang/en/message.php
index 9cced44628c4f..7f178f6649319 100644
--- a/lang/en/message.php
+++ b/lang/en/message.php
@@ -263,7 +263,7 @@
 $string['unreadnewgroupconversationmessage'] = 'New message from {$a->name} in {$a->conversationname}';
 $string['unreadnewmessage'] = 'New message from {$a}';
 $string['useentertosend'] = 'Use enter to send';
-$string['usercantbemessaged'] = 'You can\'t message {$a} due to their message preferences. Try adding them as a contact.';
+$string['usercantbemessaged'] = 'You can\'t message this user due to their message preferences. Try adding them as a contact.';
 $string['userwouldliketocontactyou'] = '{$a} would like to contact you';
 $string['viewfullnotification'] = 'View full notification';
 $string['viewmessageswith'] = 'View messages with {$a}';
diff --git a/message/externallib.php b/message/externallib.php
index a9fe992719e65..57717eded58d8 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -212,7 +212,7 @@ public static function send_instant_messages($messages = array()) {
             // Check if the recipient can be messaged by the sender.
             if ($success && !\core_message\api::can_send_message($tousers[$message['touserid']]->id, $USER->id)) {
                 $success = false;
-                $errormessage = get_string('usercantbemessaged', 'message', fullname(\core_user::get_user($message['touserid'])));
+                $errormessage = get_string('usercantbemessaged', 'message');
             }
 
             // Now we can send the message (at least try).
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index 867ff6d46be7c..832b849140aae 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -129,7 +129,7 @@ public function test_send_instant_messages(): void {
         $sentmessages = core_message_external::send_instant_messages($messages);
         $sentmessages = external_api::clean_returnvalue(core_message_external::send_instant_messages_returns(), $sentmessages);
         $this->assertEquals(
-            get_string('usercantbemessaged', 'message', fullname(\core_user::get_user($message1['touserid']))),
+            get_string('usercantbemessaged', 'message'),
             array_pop($sentmessages)['errormessage']
         );
 
@@ -225,7 +225,7 @@ public function test_send_instant_messages_blocked_user(): void {
 
         $sentmessage = reset($sentmessages);
 
-        $this->assertEquals(get_string('usercantbemessaged', 'message', fullname($user2)), $sentmessage['errormessage']);
+        $this->assertEquals(get_string('usercantbemessaged', 'message'), $sentmessage['errormessage']);
 
         $this->assertEquals(0, $DB->count_records('messages'));
     }
@@ -261,7 +261,7 @@ public function test_send_instant_messages_block_non_contacts(): void {
 
         $sentmessage = reset($sentmessages);
 
-        $this->assertEquals(get_string('usercantbemessaged', 'message', fullname($user2)), $sentmessage['errormessage']);
+        $this->assertEquals(get_string('usercantbemessaged', 'message'), $sentmessage['errormessage']);
 
         $this->assertEquals(0, $DB->count_records('messages'));
     }