I am using ImapClient by MailKit and trying to move a message from folder A to folder B after reading the message, but the message is not moved and still exists in folder A. What is the problem?

Here is my code:

using (var client = new ImapClient())
{
    client.Connect(_config.SmtpServer, _config.Port, true);
    client.Authenticate(_config.UserName, _config.Password);
    client.Inbox.Open(MailKit.FolderAccess.ReadWrite);
    var inbox = client;

    var archive = inbox.GetFolder(SpecialFolder.Archive);
    archive.Open(FolderAccess.ReadWrite);

    var A = inbox.GetFolder("A");
    A.Open(FolderAccess.ReadWrite);

    for (int i = 0; i < A.Count; i++)
    {
      if (!A.IsOpen)
          A.Open(FolderAccess.ReadWrite);
      MimeMessage message = A.GetMessage(i);
      //reading email
      //....
      A.MoveTo(i, archive); //this line doesn't affect the message
    }

    client.Disconnect(true);
}

The function A.MoveTo(i, archive) doesn’t move the email.

Thank you if you can help me in this case.