Hello @amineboulil-4635,
Are you seeing the certificate in App Service Certificates area? Make sure that the certificates are assigned correctly https://portal.azure.com/#blade/HubsExtension/Resources/resourceType/Microsoft.CertificateRegistration%2FcertificateOrders
Please mark as "Accept the answer" if the above steps helps you. Others with similar issues can also follow the solution as per your suggestion
Regards,
Manu