has been blocked by CORS policy

<?php
include('db.php');

header("Access-Control-Allow-Origin: http://localhost:19006");
header('Access-Control-Allow-Methods: GET, POST, OPTIONS');
header("Access-Control-Allow-Headers: Content-Type, Authorization");
header("Content-Type: application/json");

$UserEmail = $decodedData['Email'];
$UserPW = ($decodedData['Password']); //password is hashed

$SQL = "SELECT * FROM newuser WHERE UserEmail = '$UserEmail'";
$exeSQL = mysqli_query($conn, $SQL);
$checkEmail =  mysqli_num_rows($exeSQL);

if ($checkEmail != 0) {
    $arrayu = mysqli_fetch_array($exeSQL);
    if ($arrayu['UserPw'] != $UserPW) {
        $Message = "pw WRONG";
    } else {
        $Message = "Success";
    }
} else {
    $Message = "No account yet";
}

$response[] = array("Message" => $Message);
echo json_encode($response);

import React, { Component } from 'react';
import { View, Pressable, Text, TextInput, TouchableOpacity, Button} from 'react-native';
import stylesin from '../../style';
import Feather from 'react-native-vector-icons/Feather';

export default class signin extends Component {
  constructor(props) {
    super(props);
    this.state = {
      email : '',
      password : '',
      check_textInputChange : false,
      secureTextEntry : true,
    };
  }

  InsertRecord=()=>{
    var Email = this.state.email;
    var Password = this.state.password;

    if ((Email.length==0) || (Password.length==0)){
      alert("Required Field Is Missing!!!");
    }else{
      var APIURL = **"http://mywebsite.nl/login.php"**;

      var headers = {
        'Accept' : 'application/json',
        'Content-Type' : 'application/json'
      };
            
      var Data ={
        Email: Email,
        Password: Password
      };

      fetch(APIURL,{
        method: 'POST',
        headers: headers,
        body: JSON.stringify(Data)
      })
      .then((Response)=>Response.json())
      .then((Response)=>{
        alert(Response[0].Message)
        if (Response[0].Message == "Success") {
          console.log("true")
          this.props.navigation.navigate("HomeScreen");
        }
        console.log(Data);
      })
      .catch((error)=>{
        console.error("ERROR FOUND" + error);
      })
    }
  }

  updateSecureTextEntry(){
    this.setState({
      ...this.state,
      secureTextEntry: !this.state.secureTextEntry
    });
  }

  render() {
    return (
      <View style={stylesin.viewStyle}>
          <View style={stylesin.action}>
            <TextInput
              placeholder="Enter Email"
              placeholderTextColor="#ff0000"
              style={stylesin.textInput}
              onChangeText={email=>this.setState({email})}
              />
          </View>

          <View style={stylesin.action}>
            <TextInput
              placeholder="Enter Password"
              placeholderTextColor="#ff0000"
              style={stylesin.textInput}
              secureTextEntry={this.state.secureTextEntry ? true : false}
              onChangeText={password=>this.setState({password})}
              />
                <TouchableOpacity
                  onPress={this.updateSecureTextEntry.bind(this)}>
                  {this.state.secureTextEntry ?
                  <Feather
                  name="eye-off"
                  color="grey"
                  size={20}
                  />
                :  
                  <Feather
                  name="eye"
                  color="black"
                  size={20}
                  />
                }
                </TouchableOpacity>  
          </View>


                {/* Button */}

                <View style={stylesin.loginButtonSection}>    
                  <Pressable
                    style={stylesin.loginButton} 
                    onPress={()=>{
                      this.InsertRecord()
                    }}
                    >
                      <Text style={stylesin.text}>Sign In</Text>
                  </Pressable>
                </View>

                <View style={stylesin.loginButtonSection}>
                  <Pressable
                    style={stylesin.loginButton} 
                    onPress={()=>{
                      // this.InsertRecord()
                    }}
                    >
                      <Text style={stylesin.text}>Create new Account</Text>
                    </Pressable>
                  </View>
      </View>
    );
  }
}