I can't receive email

Hi,
Thank you for this great project and for the work you put through,
I have set up gitlab/gitlab-ce:latest in VM VirtualBox and on a private server,OS is unbuntu.
But I can use website to send email,and I can't receive email to register when using gitlab.
I have followed the steps in https://docs.gitlab.com/omnibus/docker/README.html.

sudo docker run --detach
--hostname gitlab.example.com
--publish 443:443 --publish 80:80 --publish 2289:22 \ ##I have dowload ssh so can't use 22:22
--name gitlab
--restart always
--volume /srv/gitlab/config:/etc/gitlab
--volume /srv/gitlab/logs:/var/log/gitlab
--volume /srv/gitlab/data:/var/opt/gitlab
gitlab/gitlab-ce:latest

sudo docker exec -it gitlab vi /etc/gitlab/gitlab.rb

gitlab_rails['smtp_enable'] = true
gitlab_rails['smtp_address'] = "smtp.gmail.com"
gitlab_rails['smtp_port'] = 587
gitlab_rails['smtp_user_name'] = "yoyoXXXXXX@gmail.com"
gitlab_rails['smtp_password'] = "password"
gitlab_rails['smtp_domain'] = "smtp.gmail.com" ##when I find solution,some website write "www.gamil.com"
gitlab_rails['smtp_authentication'] = "login"
gitlab_rails['smtp_enable_starttls_auto'] = true
gitlab_rails['smtp_tls'] = false
gitlab_rails['smtp_openssl_verify_mode'] = 'peer'

sudo docker restart gitlab

Am I missing something? Is there a problem with the Gmail SMTP support?

Start with the linked Docker installation documentation and the /etc/gitlab/gitlab.rb SMTP settings shown in the issue. Reproduce registration email delivery after restarting the container, and verify that the configured Gmail SMTP setup can send the registration message.