❔ SmptClient invalid response to the EHLO command.

    private async Task<bool> SendAsync(string recipientEmail, string subject, string body)
    {
        const string senderEmail = "removed"; // Your Gmail email address
        const string senderPassword = "removed"; // Your application-specific password

        SmtpClient smtpClient = new SmtpClient("smtp.gmail.com", 587);
        smtpClient.EnableSsl = true;
        smtpClient.UseDefaultCredentials = false;
        smtpClient.Credentials = new NetworkCredential(senderEmail, senderPassword);
        
        var mailMessage = new MailMessage(senderEmail, "[email protected]", "test", "test2");
        mailMessage.IsBodyHtml = true;
        
        await smtpClient.SendMailAsync(mailMessage);
    }

public class MailService
{
    private const string SenderEmail = "removed"; // Your Gmail email address
    private const string SenderPassword = "removed"; // Your application-specific password

    private readonly SmtpClient _smtpClient = new SmtpClient("smtp.gmail.com", 587);

    public MailService()
    {
        _smtpClient.EnableSsl = true;
        _smtpClient.UseDefaultCredentials = false;
        _smtpClient.Credentials = new NetworkCredential(SenderEmail, SenderPassword);
    }

    public async Task<bool> SendAsync(string recipientEmail, string subject, string body)
    {
        var mailMessage = new MailMessage(SenderEmail, recipientEmail, subject, body);
        mailMessage.IsBodyHtml = true; 

        await _smtpClient.SendMailAsync(mailMessage);
    }
}