According to the Wikipedia French page for this show, quoting Télé Star, 3 septembre 2016 and Alexandra Schwartzbrod, « Micky Sebastian, l'instinct de (sur)vie » (archive), sur Libération, 2 novembre 2015 (consulté le 18 août 2018)., the producers fired Sebastien because she wouldn't agree to wardrobe and hair changes; basically, they were trying to make her look younger. So she was fired because they thought she was too old.