LINE BOT PHP ไม่สามารถ reply message ได้ ก่อนหน้านี้ใช้งานได้ปกติ

<?php
$strAccessToken = "xxxxxxxxxxxxxxx";
 

$content = file_get_contents('php://input');
$arrJson = json_decode($content, true);
 
$strUrl = "https://api.line.me/v2/bot/message/reply";
 
$arrHeader = array();
$arrHeader[] = "Content-Type: application/json";
$arrHeader[] = "Authorization: Bearer {$strAccessToken}";
 
 if($arrJson['events'][0]['message']['text'] == "Hello"){
  $arrPostData = array();
  $arrPostData['replyToken'] = $arrJson['events'][0]['replyToken'];
  $arrPostData['messages'][0]['type'] = "text";
  $arrPostData['messages'][0]['text'] = "สวัสดีครับ";
}

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$strUrl);
curl_setopt($ch, CURLOPT_HEADER, false);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $arrHeader);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($arrPostData));
curl_setopt($ch, CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
$result = curl_exec($ch);
curl_close ($ch);

?>