O-M-G : it’s workiiiiiing !!! 
Finally, after the automatic assistant from SOSH failed, they end up calling me and they find out that my problem did come from my APN.
If it can help, I share here he settings working for me:
- For internet :
- For MMS :
I changed the authentification type : I had none - I turn it into PAP.
@smu44 : thank you again A LOT for your help and the time you spent trying to find out a solution to my problem 