STMP doesn't work

I used SMTP for opencart 3.0.2.0. But shows below errors.

Warning: fsockopen(): unable to connect to ssl://smtp.gmail.com:465 (Network is unreachable) in /home/####/public_html/system/library/mail/smtp.php on line 87
Fatal error: Uncaught exception 'Exception' with message 'Error: Network is unreachable (101)' in /home/####/public_html/system/library/mail/smtp.php:90 Stack trace: #0 /home/####/public_html/system/library/mail.php(142): Mail\Smtp->send() #1 /home/#####/#####/modification/catalog/controller/mail/register.php(94): Mail->send() #2 [internal function]: ControllerMailRegister->index('account/custome...', Array, 13) #3 /home/#####/public_html/vqmod/vqcache/vq2-_home_#####_#####_modification_system_engine_action.php(79): call_user_func_array(Array, Array) #4 /home/####/public_html/system/engine/event.php(62): Action->execute(Object(Registry), Array) #5 /home/####/public_html/vqmod/vqcache/vq2-_home_####_####_modification_system_engine_loader.php(255): Event->trigger('model/account/c...', Array) #6 [internal function]: Loader->{closure}(Array, Array) #7 /home/#####/public_html/system/engine/proxy.php(47): call_user_func_array(Object(Closure), Array) #8 /home/####/#####/modifi in /home/####/public_html/system/library/mail/smtp.php on line 90

Anyone can help me?

Have used the search before?
Countless questions about this, and a few (working) solutions:
search.php?keywords=gmail%7Csmtp&terms= ... Search&t=0

Searching all smtp related post, I couldn't find any right solution from now.
If anyone knows what to do. Please help.
I also try changing SMTP Hostname ssl://smtp.gmail.com to smtp.gmail.com.
But the same error occurs.

When you think you must use GMail and not your own shop smtp, it is up to you to look where and how these settings are.
But when I read the manual at GMail for external access, I see for example:

Port for SSL: 465
Port for TLS/STARTTLS: 587

Just one setting.

So, I would try it with and port 587

Anf if that does not help, post a request in the commerical forum here.

btw: it is highly unprofessional to send email via GMail and not over your shop account. The majority will not understand the difference, but some will do.