Android build, wwwform gives ssl.SSLHandshakeException

So, I have this code in the editor:

string email = ifemail.text;
string pssw = ifpassw.text;
WWWForm form = new WWWForm();
form.AddField("email", email);
form.AddField("password", pssw);
WWW w = new WWW("https://myserverpath/action_login.php", form);  
 
yield return w;  

if (string.IsNullOrEmpty(w.error))
{
      if (w.text.Contains("invalid email or password"))
      {
               		 // wrong data
      } else
      {
              		  // login successful --> Return this in editor
      }
} else
{
            // comunication error --> return this in apk
}

It works perfectly fine in the editor and I can both access and write on the db (so the php files work both for login and registration and db connection). Just in case this is the php code for login and connection:
LOGIN :

<?php
include '../dbconnect.php';

$email = $_POST['email'];
$upass = $_POST['password'];

$email = strip_tags($email);
$upass = strip_tags($upass);

$query = "SELECT userEmail FROM users WHERE userEmail='$email' AND userPass='$upass'";
$result = mysqli_query($dbconnection, $query);

$row = mysqli_fetch_row($result);
if($row) {
	$dataArray = array('success' => true, 'error' => "$email");
} else {
	$dataArray = array('success' => false, 'error' => 'invalid email or password');
}

header('Content-Type: application/json');
echo json_encode($dataArray);

?>

CONNECT :

<?php
$dbuser = 'test_user';
$dbpassword = 'blurredpassword';
$db = 'test_db';
$dbhost = 'XXX.XXX.X.XXX';

$dbconnection = mysqli_connect($dbhost, $dbuser, $dbpassword, $db) or die("Connection failed " . mysql_error());

?>

If i build my apk, I cannot even get to connect to db. I searched for answers all around, but can’t find a resolutive answer

I have internet access required in player settings, no custom manifest and tried both “https” and “http”

What am I missing? please help meh…

I just run on the debugger and I get this :

09-04 16:20:40.226 26328 26359 E Unity   : javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found.
    09-04 16:20:40.226 26328 26359 E Unity   :
    09-04 16:20:40.226 26328 26359 E Unity   : (Filename:  Line: 435)
    09-04 16:20:40.226 26328 26359 E Unity   :
    09-04 16:20:40.226 26328 26341 I Unity   : Error occurred :Unknown Error
    09-04 16:20:40.226 26328 26341 I Unity   :
    09-04 16:20:40.226 26328 26341 I Unity   : (Filename: ./Runtime/Export/Debug.bindings.h Line: 43)
    09-04 16:20:40.226 26328 26341 I Unity   :

Could it be related to the server provider? I’m not really an expert, but I read online it’s a certification issue… is it solvable?