immatriculation travailleurs étrangers

Good morning,
I am a PhD student and I started to work in Dijon from the beginning of March. Since is mandatory to have a social security number to work in France I did the application on this website https://immatriculation-travailleurs-etrangers.ameli.fr/f..., receiving a provisional social security number. In the mail that I received it is written that I cannot open an Amelie account and I cannot have a Vitale card with that number. I tried to do also the access on my dossier at this website https://affiliation-production.digital.cnamts.fr/ but it never worked.
The company has proposed to me to do a heath insurance but they request an attestation de droit and a copy of the Vitale card that I still not have. Will I receive a definitive social security number and my card Vitale or have I to do something else?
Thank in advance