echo json_encode($response) fungerar inte react.js

<?php

header('Access-Control-Allow-Origin: *'); 
header("Access-Control-Allow-Credentials: true");
header('Access-Control-Allow-Methods: GET, PUT, POST, DELETE, OPTIONS');
header('Access-Control-Max-Age: 1000');
header('Access-Control-Allow-Headers: Origin, Content-Type, X-Auth-Token , Authorization');
include("connect.php");


$rest_json = file_get_contents("php://input");
$_POST = json_decode($rest_json, true);


if( !empty($_POST['loginEmail']) && !empty($_POST['loginPassword'])) 
{

	http_response_code(200);
       
	$email = $_POST['loginEmail'];
	$password = $_POST['loginPassword'];
	
	$sql = "SELECT email FROM User WHERE email='$email'";

	$result = mysqli_query($connect, $sql) or die("Query died: loginEmail");
	$num = mysqli_num_rows($result);

	if($num >0)  
	{
		$sql = "SELECT password FROM password WHERE password='$password' AND userid = (SELECT userid FROM user WHERE email='$email') ";
		$result2 = mysqli_query($connect, $sql) or die("Query died: loginPassword");
		$num2 = mysqli_num_rows($result2);

		if($num2 > 0)
		{
			
			$_SESSION['auth']="yes";
			$_SESSION['logname'] = $_POST['loginEmail'];
			$sql = "INSERT INTO Login (loginName, loginTime) VALUES ('$_SESSION[logname]' ,NOW())";

			$result3 = mysqli_query($connect, $sql) or die("Query died: insert");
			$num3 = mysqli_num_rows($result3);

			$response = 'true';
			echo json_encode($response);

			if($num3 > 0)
			{
				$email = $_POST['loginEmail'];
				$sql = "SELECT userid FROM User WHERE email='$email'";

				$result3 = mysqli_query($connect, $sql) or die("Query died: insert");

				$result = $connect ->query($sql);
				$return_arr = array();

				if($result = mysqli_query($connect, $sql))  {
					while($row = mysqli_fetch_assoc($result)) {
						$row_array['userid'] = $row['userid'];
						$response = $row['userid'];
						array_push($return_arr, $row_array);
					}
				}    
				echo json_encode($return_arr);
				mysqli_close($connect);*/
			}	
		}
		else {
			$message_1 = "The Login Name, '$_POST[loginEmail]'
				exists,but you have not entered the correct password! PLease tyr again.";
				$loginEmail=strip_tags(trim($_POST['loginEmail']));
				$response = "false";
				echo json_encode($response);	
		}
	}
	else {
		$message_1 = "The User Name you entered does not exists! Please try again.";
		$response = "false";
		echo json_encode($response);
	}
}

?>

    loginSubmit(event) {

        event.preventDefault();

        const data = {
            loginEmail: this.refs.loginEmail.value,
            loginPassword: this.refs.loginPassword.value
        }
  
        fetch('http://localhost/reusesport/src/api/login.php', {
            method: 'POST',
            body: JSON.stringify(data),
        })
        .then(response => {
            console.log(response);

            if(response === 'true') {
                this.props.history.push(`/MySide/:user`);
            } else {
                console.log('felaktigt lösenord');
            }
        }) 
   
        event.target.reset();
    }