Onesignal notification api stopped sending when added Huawei - php

Question

I have php api for Onesingal notifications to send notification to users when I approve post on my app, it was working perfectly until I added new platform on Onesingal Dashboard which is Huawei, then when I tried to send notification from the app it does't send!
I noticed in the Dashboard that Huawei requires title to send notification! and title already on my api ! but I cann't figure it out!
Notification image
<?php
$title = $_REQUEST["title"];
$sendnotification = $_REQUEST["sendall"];
//here it sends to the post owner that his post is approved
//if ($_SERVER['REQUEST_METHOD'] == 'POST'){
if($isApproved=="1")
{
$ph=$phone;
$arr = $mysqli->query("select * from users where phone='$ph'")->fetch_array(MYSQLI_ASSOC);
$player_id = $arr["token"];
if(!empty($player_id)) {
$content = array(
"en" => "Your post is approved"
);
$heading = array(
"en" => "Your post is approved"
);
$fields = array(
'app_id' => "xxxxxx-xxxxxx-xxxx-xxxx-xxxxxxxxx",
'include_player_ids' => array($player_id),
'contents' => $content
);
$fields = json_encode($fields);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://onesignal.com/api/v1/notifications");
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json; charset=utf-8',
'Authorization: Basic xxxxxxxxxxxxxxxxxxxxxxxxxxxx'));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_HEADER, FALSE);
curl_setopt($ch, CURLOPT_POST, TRUE);
curl_setopt($ch, CURLOPT_POSTFIELDS, $fields);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
$one2 = curl_exec($ch);
curl_close($ch);
}
}
// here it sends notification fo all users with the post title
if ($isApproved=="1"&& $sendnotification=="1")
{
$content = array(
"en" => $title
);
$heading = array(
"en" => $title
);
$fields = array(
'app_id' => "xxxxxx-xxxxxx-xxxx-xxxx-xxxxxxxxx",
'included_segments' => array('All'),
'contents' => $content
);
$fields = json_encode($fields);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://onesignal.com/api/v1/notifications");
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json; charset=utf-8',
'Authorization: Basic xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_HEADER, FALSE);
curl_setopt($ch, CURLOPT_POST, TRUE);
curl_setopt($ch, CURLOPT_POSTFIELDS, $fields);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
$one2 = curl_exec($ch);
curl_close($ch);
echo $one2;
}
//}
echo json_encode($se);
?>