Hi MathieuBURET,
Thanks for replying! In general, unless you otherwise specify a different email address be used, any emails sent to you from Xbox Support will go to the email address associated with your email alias used to log into your Microsoft account.
If you have received an email from the support advocate, in order to contact them directly, simply reply directly to the email you received to ask any questions or let them know you have not received contact/information from the Service Center so that
they can further assist you. Should you wish them to contact you directly by phone, please indicate you wish them to do so and provide a good date, time and phone number to call you at.
If you do not receive a reply from the agent in 48 hours, I would recommend that you
request a call back from support again and reference your service request number (located in the subject line of the email you received beginning with SRX) to receive any updates
or to get further assistance. Please note that you may also check on the status of your request via your Microsoft account under Device support.
Help with your existing Xbox console or accessory service order
I hope that this information helps you out a bit more. Let us know the results!