Hi follow this link
Nokia 2go app. download and do what instruction is provided.But first you should have a Nokia Account.All the details procedure are given in this link.Thanks for visiting fixya
You need to contact the helpline number of your network operator and ask them for the settings.they will send you the settings save it and activate it as default in your mms settings.
please vote me if i had helped.
You can get the Restriction code from service provider.