Email Vérification issue

Hi, all Laravel Enthusiast out there, I struggled for a while with the following issue and looked for a solution but nothing won't work. I hope to find an explanation to solve this for you.

Here are the cases:

I want to enable email verification while the user registers his account but I'm using a local mail server. The issue is the users who don't belong to the org where I work don't receive the mail on the other hand my teammates received it.

Below is mail received when a user with for example @gmail.com tries to register:

This is the mail system at host mail.example.ma.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

               The mail system

[email protected]: host gmail-smtp-in.l.google.com[66.102.1.26] said: 550-5.7.1 [xxx.xx.xxx.xx] The IP you're using to send mail is not authorized to 550-5.7.1 send email directly to our servers. Please use the SMTP relay at your 550-5.7.1 service provider instead. For more information, go to 550 5.7.1 https://support.google.com/mail/?p=NotAuthorizedError 5b1f17b1804b1-4215c19ab08si23271325e9.233 - gsmtp (in reply to end of DATA command)

I'm appreciated to any support to solve this issue.