Name Change

When my son was born his mother gave him a name, first and last. @ months after his birth we found out he was in fact my son. We went to the local municipal office in our town to change his name. They said we could change it one time in their office but after that we wwould have to go to court.

Now 2 years later his mother never changed the social security card. In trying to accomplish this we are beeing told to bring in the court papers proving the name change. However there are no court papers as it was done at the municipal office. My son is almost 3 and has no photo id or any other identifying documents other then his birth certificate which has his new name on it.

The office of social security has given us 3 different scenarios of identifying my son by three different workers. On one occasion a worker told us to simply bring in the birth certificate and that would suffice. On returning a different worker assisted us and said that was insufficient.

Is it the luck of the draw with who you are dealing with on any particular day at the social security office or is there a set way to have my sons social security card changed to the correct name? any help would be greatly appreciated.