Reply by mail - Not Working

In order to Configure reply by email ( For committing Issue From mail Reply )Trying to Configure using the following Reference

Also, I use a Gsuite Account

My Sample Configuration

### Reply by email
###! Allow users to comment on issues and merge requests by replying to
###! notification emails.
###! Docs: https://docs.gitlab.com/ce/administration/reply_by_email.html
gitlab_rails['incoming_email_enabled'] = true

#### Incoming Email Address
####! The email address including the `%{key}` placeholder that will be replaced
####! to reference the item being replied to.
####! **The placeholder can be omitted but if present, it must appear in the
####!   "user" part of the address (before the `@`).**
gitlab_rails['incoming_email_address'] = "example+%{key}@gmail.com"

#### Email account username
####! **With third party providers, this is usually the full email address.**
####! **With self-hosted email servers, this is usually the user part of the
####!   email address.**
gitlab_rails['incoming_email_email'] = "example@gmail.com"
#### Email account password
gitlab_rails['incoming_email_password'] = "mypassword"

#### IMAP Settings
gitlab_rails['incoming_email_host'] = "imap.gmail.com"
gitlab_rails['incoming_email_port'] = 993
gitlab_rails['incoming_email_ssl'] = true
gitlab_rails['incoming_email_start_tls'] = false

#### Incoming Mailbox Settings
####! The mailbox where incoming mail will end up. Usually "inbox".
gitlab_rails['incoming_email_mailbox_name'] = "inbox"
####! The location where incoming mails will be logged.
gitlab_rails['incoming_email_log_directory'] = "/var/log/gitlab/mailroom"

# The IDLE command timeout.
gitlab_rails['incoming_email_idle_timeout'] = 60

Configuration Verification

gitlab-rake gitlab:incoming_email:check

Checking Incoming Email ...

Incoming Email: ... Checking Reply by email ...

IMAP server credentials are correct? ... no
  Try fixing it:
  An error occurred: Errno::ENETUNREACH: Network is unreachable - connect(2) for [2404:6800:4003:c02::6d]:993
  Check that the information in config/gitlab.yml is correct
  For more information see:
  doc/administration/reply_by_email.md
  Please fix the error above and rerun the checks.
Init.d configured correctly? ... skipped
MailRoom running? ... skipped

Checking Reply by email ... Finished


Checking Incoming Email ... Finished

My Gitlab Information

Operating System - Centos 7
Edition - Gitlab CE
Version - GitLab 11.9.1
Installation Method - Omnibus package Installation
Access - Configured For Intranet users only.