Hello, I'm using liferay 7.4

I configure mail property through control panel > system administration > mail

In my local pc in window,  i successfully receive mail. But when I put my portlet to server ubuntu (install liferay using docker), I not successfully receive the mail. Eventhouh error message also not produce inside log

My code in portlet is in below

private void sendMailMessage(
            ActionRequest actionRequest, ActionResponse actionResponse, String mailFrom, String mailTo, String title, String body)
				throws IOException, PortletException {
				String mailSubject=title;
				String mailBody=body;
				String senderMailAddress=mailFrom;
				String receiverMailAddress=mailTo;
				try {
				            MailMessage mailMessage=new MailMessage();
				            mailMessage.setBody(mailBody);
				            mailMessage.setSubject(mailSubject);
				            mailMessage.setFrom(new InternetAddress(senderMailAddress));
				            mailMessage.setTo(new InternetAddress(receiverMailAddress));
				            MailServiceUtil.sendEmail(mailMessage);
				    // SessionMessages.add((HttpServletRequest) actionRequest.getPortletSession(),"mail-send-success");
				}
				catch (Exception e) {
				    e.printStackTrace();
				}
	}

What should I do now so that I can receive mail service successfully. Thanks