
After raising this issue on this site, my AD also offered to send my purchased 5370P back to Switzerland for checking. There was no particular problem, but I entrusted it to my AD.
It came back in about 3 months with the crown and pusher replaced with new ones. There was no charge as it was under warranty.
There was a possibility that airtightness could not be secured in some parts, so it was explained that it was resolved.