The first certificate of application for asylum in the Dublin procedure is valid for one month. If the Dublin procedure is still being processed, you must renew it a few days before your certificate expires. You must also request the renewal of your certificate if you change your address. You can also use this procedure if your certificate is lost or stolen.
Please note: All asylum certificates that initially expire between 16 March and 15 June 2020 are automatically extended by 90 days. You should not come to the prefecture before this new expiry date.
The renewal procedure, for asylum seekers placed in a Dublin procedure and accommodated in the whole Normandy region, depends on the prefecture in Rouen.

Obtaining an appointment

You must now make an appointment before coming to the prefecture to renew your asylum seeker's. To obtain an appointment, click here.

http://www.seine-maritime.gouv.fr/Prendre-un-rendez-vous-en-ligne/Prefecture-de-la-Seine-Maritime-Rouen

This guide explains how to do this in a few minutes:

This service is exclusively reserved for asylum seekers in Dublin procedure in the following situations:

• you wish to renew your attestation of asylum application which is about to expire;
• you wish to modify your certificate following a change of address;
• you wish to obtain a duplicate of your asylum application certificate, in case of loss or theft (declaration of loss or theft obligatory).
• You must make an appointment for each certificate to be renewed.

To make an appointment, you will need a valid e-mail address and your 10-digit identifier from your asylum application certificate.
You can only make an appointment if you are living or staying in the Normandy region.

Please note: All asylum certificates which initially expire between 16 March and 15 June 2020 are automatically extended by 90 days. You should not come to the prefecture before this new expiry date.