为什么ActionScript到PHP失败插入查询和cURL有时？

I'm creating games in Flash with ActionScript 3.0. I'm passing data to PHP to check, insert game result and send request to an API URL.

But, I'm experiencing of some failed insert query, some failed cURL and both sometimes? Why was it?

I'm using RDS Database(t2.Medium).

Here's my code in ActionScript:

var variables:URLVariables = new URLVariables();

var varSend:URLRequest = new URLRequest(link + "parse.php");
varSend.method = URLRequestMethod.POST;
varSend.data = variables;

// Build the varLoader variable

var varLoader:URLLoader = new URLLoader;
varLoader.dataFormat = URLLoaderDataFormat.BINARY;

//varLoader.addEventListener(Event.COMPLETE, completeHandler);

variables.apikey = "<API KEY>";
variables.username = <FETCH FROM JS>
variables.side = "Good";



variables.player1 = player1;
variables.player2 = player2;
variables.player3 = player3;
variables.player4 = player4;
variables.player5 = player5;

variables.jackpot1 = jackpot1;
variables.jackpot2 = jackpot2;
variables.jackpot3 = jackpot3;
variables.jackpot4 = jackpot4;
variables.jackpot5 = jackpot5;
variables.sendRequest = "parse";

// Send the data to the php file

varLoader.load(varSend);

Here's my code in PHP:

<?php

if ($_POST['sendRequest'] == "parse") {


$datetime = date('Y-m-d H:i:s');
$datetime1 = date('Y-m-d');

$apikey = $_POST['apikey'];

$promocode = "TestGame";
$username = $_POST['username'];

$alignment = $_POST['side'];
$player1 = $_POST['player1'];
$player2 = $_POST['player2'];
$player3 = $_POST['player3'];
$player4 = $_POST['player4'];
$player5 = $_POST['player5'];
$player = $player1 + $player2 + $player3 + $player4 + $player5;


$jackpot1 = $_POST['jackpot1'];
$jackpot2 = $_POST['jackpot2'];
$jackpot3 = $_POST['jackpot3'];
$jackpot4 = $_POST['jackpot4'];
$jackpot5 = $_POST['jackpot5'];
$jackpot = $jackpot1 + $jackpot2 + $jackpot3 + $jackpot4 + $jackpot5;

$db_servername = "<RDS Host>";
$db_username = "<Database User>";
$db_password = "<DB Password>";
$db_name = "<DB Name>";


$connection = mysqli_connect($db_servername, $db_username, $db_password, $db_name);
if (mysqli_connect_errno()) {
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$check_sql = "SELECT * FROM tblpoints WHERE username = '$username' AND date(datetime) = '$datetime1'";
$result = mysqli_query($connection,$check_sql);
if (!$result) {
    echo "Error in checking record: " + mysqli_error($connection);
    exit;
}

$points = $player;
$betcondition = $points * 10;

$ch = curl_init();

curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: application/json")); 

curl_setopt($ch,CURLOPT_URL, "<API URL>".$points."/".$betcondition."/".$username);
curl_setopt($ch,CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch,CURLOPT_POST,1);


curl_setopt($ch,CURLOPT_SSL_VERIFYHOST,FALSE);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch,CURLOPT_SSL_VERIFYPEER,FALSE);

$result = curl_exec($ch); 

if(curl_errno($ch)) {
    print "Error: " . curl_error($ch);
} else {
    curl_close($ch);
}

$sql = "INSERT INTO tblpoints (username, alignment, player_points, player_points1, player_points2, player_points3, player_points4, player_points5, jackpot_points, jackpot_points1, jackpot_points2, jackpot_points3, jackpot_points4, jackpot_points5, datetime, status) VALUES ('$username', '$alignment', '$player', '$player1', '$player2', '$player3', '$player4', '$player5', '$jackpot', '$jackpot1', '$jackpot2', '$jackpot3', '$jackpot4', '$jackpot5', '$datetime', '$status')";
mysqli_query($connection,$sql);
mysqli_close($connection);
}
?>

Note: There will be no direct input from users here.

I actually figured out what really happening in my codes. The Actionscript function I created was being delayed from processing it to PHP.

The user must not close the browser window and need to wait for the script to finish. So, what I did was display a Loading Message and hide after AS function completed.