Go Plus - no signal!

Help!! I received the below message this morning and since then I have no signal!!! I restarted my phone several times but nothing!! Maybe it's because I'm not in Belgium but I can't go back for two weeks!! Please let me know if you know how to solve the problem, I need my GSM for telework!!!

"Info Orange. Votre abonnement mobile devient Go Plus. Si le signal réseau disparait durant le changement veuillez redémarrer votre téléphone et toute rentrera dans l'ordre."