I tried a new user from the scratch. I added the user into IT@ group.
I've sent an email and I saw the email in the outlook.
When i tried the refresh-mailbox command there aren't any emails in the UVDESK.

Unfortunately i can't do that. I will create a new user as a member of the IT@ email group and I'll let you know

No it doesn't converted.

1. I delete everything from the italerts mailbox.
2. I sent an email to IT@ and the italerts receive it.
3. Restart Apache.
4. Clear cache ( php bin/console c:c )
5. Run the refresh command. (below is the screenshot)
   
6. Nothing appeared in the Tickets link of UVDesk

Yes that's true. I tried several Helpdesk systems before and all of them worked with fine with this.

No unfortunately not. Actually i tried a lot of things before sent a request to the forum.
For example i deleted all the emails from the italerts mailbox , sent a new email to IT group , where italerts is a member , but i didn't receive it.
By the way everything else works fine. Customers created automatically, refresh mailbox works well too when it counts the emails.

Vipin,
i've done what you suggest but it doesn't work

I mean that when i refresh mailbox the i am receiving the emails of the italerts mailbox and not the emails of the IT group that the italerts mailbox is member.

Thank you for the reply. As for the "Syntax Error" corrected according to your suggestion.
The mail issue still remains. I am getting the emails/tickets of the mailbox and of the group that the mailbox belongs to.