French citizenship through filiation

Hi,
I have been trying to obtain French citizenship through the consulate but have been getting asked for one set of documents after the other.

My mother holds dual American and French citizenship but was born in the US, her mother, my grandmother was French and born in France.

The current problem now Is she hasn't kept up with her paperwork with the French. I am having to register her divorce of 30 years ago in order to register her marriage to my dad and then me as her child. and they keep asking for absurd things that no one would have access to from that long ago. They are trying to make it impossible.

So now I'm thinking I might need to find a lawyer or someone to advocate on my behalf to try and get this accomplished does anyone have any advice on what I can do or whom I should contact?

Any help or advice anyone can offer would be much appreciated!!!!
Thanks