Email reciever

Hi,
I would like to recieve mail in my application. I found a NuGet Library called MailKit.
The problem is that after starting the application it locks on the ssl certificate.

public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();
            using (var client = new ImapClient())
            {
                client.Connect("imap.gmail.com", 993, true);

                client.Authenticate("test@tecnosoft.eu", "Tecnosoft89");

                // The Inbox folder is always available on all IMAP servers...
                var inbox = client.Inbox;
                inbox.Open(FolderAccess.ReadOnly);

                Console.WriteLine("Total messages: {0}", inbox.Count);
                Console.WriteLine("Recent messages: {0}", inbox.Recent);

                for (int i = 0; i < inbox.Count; i++)
                {
                    var message = inbox.GetMessage(i);
                    Console.WriteLine("Subject: {0}", message.Subject);
                }

                client.Disconnect(true);
            }
        }
    }

the error is:

MailKit.Security.SslHandshakeException: 'An error occurred while attempting to establish an SSL or TLS connection.

The server's SSL certificate could not be validated for the following reasons:
• Ssl error:1000007d:SSL routines:OPENSSL_internal:CERTIFICATE_VERIFY_FAILED
at /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/boringssl/ssl/handshake_client.c:1132
'

Thankou in advance,
David.