PHP - Cuando me envían mensaje a través del formulario, me llega todo menos el mensaje

echo $contents;

<form id="cntct" class="frmt-1" action="sendemail.php" method="post" enctype="multipart/form-data">

<form id="cntct" class="frmt-1" action="sendemail.php" method="post">

<input type="submit" value="Enviar Mensaje" id="btnSend">

<input type="button" value="Enviar">

<!--Pon type submit así-->

<input type="submit" value="Enviar">

<!--Deja el tag del form así -->

<form id="cntct" class="frmt-1" action="sendemail.php" method="post">

<div class="col-sm-12 col-md-8">

  <form id="cntct" class="frmt-1" action="sendemail.php" method="post">

  <fieldset>

    <h3 class="latol text-center text-sm-left"><small>Formulario de consultas</small></h3>

    <div class="row">

      <div class="col-sm-6">

        <label>Nombre:</label>

        <div class="controls error-flotante"><input type="text" name="name" autofocus></div>

      </div>

      <div class="col-sm-6">

        <label>Correo:</label>

        <div class="controls error-flotante"><input type="text" name="email"></div>

      </div>

      <div class="col-sm-6">

        <label>Teléfono:</label>

        <div class="controls"><input type="text" name="phone"></div>

      </div>

      <div class="col-sm-6">

        <label>Ciudad:</label>

        <div class="controls"><input type="text" name="city"></div>

      </div>

    </div>

    <label>Asunto:</label>

    <div class="controls error-flotante"><input type="text" name="subject"></div>

    <label>Mensaje:</label>

    <div class="controls error-flotante"><textarea name="message"></textarea></div>

    <input type="submit" value="Enviar">

    <div class="alert alert-success d-none" id="msg1Success">El mensaje ha sido enviado correctamente.</div>

    <div class="alert alert-danger d-none" id="msg1Error">No se pudo enviar el mensaje.<br />Espere unos minutos e inténtelo de

  nuevo.</div>

    <div class="alert alert-info d-none" id="msg1Info">Procesando datos...</div>

  </fieldset>

</form>

function sack(file){

	this.AjaxFailedAlert = "Your browser does not support the enhanced functionality of this website, and therefore you will have an experience that differs from the intended one.\n";

	this.requestFile = file;

	this.method = "POST";

	this.URLString = "";

	this.encodeURIString = true;

	this.execute = false;

	this.onLoading = function() { };

	this.onLoaded = function() { };

	this.onInteractive = function() { };

	this.onCompletion = function() { };

	this.createAJAX = function() {

		try {

			this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");

		} catch (e) {

			try {

				this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");

			} catch (err) {

				this.xmlhttp = null;

			}

		}

		if(!this.xmlhttp && typeof XMLHttpRequest != "undefined")

			this.xmlhttp = new XMLHttpRequest();

		if (!this.xmlhttp){

			this.failed = true;

		}

	};

	this.setVar = function(name, value){

		if (this.URLString.length < 3){

			this.URLString = name + "=" + value;

		} else {

			this.URLString += "&" + name + "=" + value;

		}

	}

	this.encVar = function(name, value){

		var varString = encodeURIComponent(name) + "=" + encodeURIComponent(value);

	return varString;

	}

	this.encodeURLString = function(string){

		varArray = string.split('&');

		for (i = 0; i < varArray.length; i++){

			urlVars = varArray[i].split('=');

			if (urlVars[0].indexOf('amp;') != -1){

				urlVars[0] = urlVars[0].substring(4);

			}

			varArray[i] = this.encVar(urlVars[0],urlVars[1]);

		}

	return varArray.join('&');

	}

	this.runResponse = function(){

		eval(this.response);

	}

	this.runAJAX = function(urlstring){

		this.responseStatus = new Array(2);

		if(this.failed && this.AjaxFailedAlert){

			alert(this.AjaxFailedAlert);

		} else {

			if (urlstring){

				if (this.URLString.length){

					this.URLString = this.URLString + "&" + urlstring;

				} else {

					this.URLString = urlstring;

				}

			}

			if (this.encodeURIString){

				var timeval = new Date().getTime();

				this.URLString = this.encodeURLString(this.URLString);

				this.setVar("rndval", timeval);

			}

			if (this.element) { this.elementObj = document.getElementById(this.element); }//else{alert(this.element);}

			if (this.xmlhttp) {

				var self = this;

				//alert(this.method);

				if (this.method == "GET") {

					var totalurlstring = this.requestFile + "?" + this.URLString;

					this.xmlhttp.open(this.method, totalurlstring, true);

				} else {

					this.xmlhttp.open(this.method, this.requestFile, true);

				}

				if (this.method == "POST"){

  					try {

						this.xmlhttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded')

					} catch (e) {}

				}

				this.xmlhttp.send(this.URLString);

				this.xmlhttp.onreadystatechange = function() {

					switch (self.xmlhttp.readyState){

						case 1:

							self.onLoading();

						break;

						case 2:

							self.onLoaded();

						break;

						case 3:

							self.onInteractive();

						break;

						case 4:

							self.response = self.xmlhttp.responseText;

							self.responseXML = self.xmlhttp.responseXML;

							self.responseStatus[0] = self.xmlhttp.status;

							self.responseStatus[1] = self.xmlhttp.statusText;

							self.onCompletion();

//							alert(self.response);

							if(self.execute){ self.runResponse(); }

							if (self.elementObj) {

								//var elemNodeName = self.elementObj.nodeName;

								//elemNodeName.toLowerCase();

								/*if (elemNodeName == "input" || elemNodeName == "select" || elemNodeName == "option" || elemNodeName == "textarea"){

									self.elementObj.value = self.response;*/

								//} else {

									self.elementObj.innerHTML = self.response;

								//}

							}

							self.URLString = "";

						break;

					}

				};

			}

		}

	};

this.createAJAX();

}

<?php

    // Only process POST reqeusts.

    if ($_SERVER["REQUEST_METHOD"] == "POST") {

        // Get the form fields and remove whitespace.

        $name = strip_tags(trim($_POST["name"]));

				$name = str_replace(array("\r","\n"),array(" "," "),$name);

        $email = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL);

        $message = trim($_POST["message"]);

        // Check that data was sent to the mailer.

        if ( empty($name) OR empty($message) OR !filter_var($email, FILTER_VALIDATE_EMAIL)) {

            // Set a 400 (bad request) response code and exit.

            http_response_code(400);

            echo "Oops! There was a problem with your submission. Please complete the form and try again.";

            exit;

        }

        // Set the recipient email address.

        // FIXME: Update this to your desired email address.

        $recipient = "ventas@icynperuana.com";

        // Set the email subject.

        $subject = "New contact from $name";

        // Build the email content.

        $email_content = "Name: $name\n";

        $email_content .= "Email: $email\n\n";

        $email_content .= "Message:\n$message\n";

        // Build the email headers.

        $email_headers = "From: $name <$email>";

        // Send the email.

        if (mail($recipient, $subject, $email_content, $email_headers)) {

            // Set a 200 (okay) response code.

            http_response_code(200);

            echo "Thank You! Your message has been sent.";

        } else {

            // Set a 500 (internal server error) response code.

            http_response_code(500);

            echo "Oops! Something went wrong and we couldn't send your message.";

        }

    } else {

        // Not a POST request, set a 403 (forbidden) response code.

        http_response_code(403);

        echo "There was a problem with your submission, please try again.";

    }

?>