SMTP configuration problem with Gmail server

Hi all, I work with Nextcloud since 2019, and after some adjustments, all works fine.
Recently I reinstall the server with ubuntu server 22.04 LTS and the newest rev. of nextcloud (24.0.5), PHP 8.1.2.
Thanks to my previous experience my first installation was better and easier than in the past.
But in this rev. I have some problems with the SMTP server configured with Gmail (I think the easiest part). I’m sure my Gmail configuration data are correct. I use these with other apps.
Server gives me the error:

First of all, why my account is converted in xxx@localhost.localdomain ?
Anyone can help me ?

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