what is the problem in my Code ?

Hello
i have Arduino and PHP codes
when i press turn on light is turne on
but when i press turn off light dosnt turn off stay on

ARDUINO CODE

int ledpin=13;
int incomingbyte;
int count=0;
void setup(){
Serial.begin(9600);
pinMode(ledpin,OUTPUT);
}
void loop(){
if(Serial.available()!=0) {
incomingbyte=Serial.read();
Serial.write( incomingbyte );
if(incomingbyte==‘0’){
digitalWrite(ledpin,HIGH);
}
if(incomingbyte==‘1’) {
digitalWrite(ledpin,LOW);
}

}

}

PHP CODE

<?php if(isset($_GET['action'])){ require("php_serial.class.php"); $serial=new phpSerial(); $serial->deviceSet("COM1"); $serial->confBaudRate(9600); $serial->deviceOpen(); if($_GET['action']=='1') { $serial->sendMessage("0\r"); print($_GET['action']); } else if ($_GET['action']=='0') { $serial->sendMessage("1\r"); print($_GET['action']); } $serial->deviceClose(); } header("Location: index.html"); // Return to frontend (index.html) ?>

http://forum.arduino.cc/index.php?topic=294952.msg2058463#msg2058463

DO NOT CROSS-POST, CROSS-POSTING WASTES TIME.

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