Number one is definitely correct

On your side sounds like te correct answer.

Hi, 1st is the more correct of the two. Be careful though as this can be confused to mean that some documents are excellent on your side, rather than unfinished or incomplete. If you want to make sure there is no confusion then change the sentence slightly if there is no context around the statement. "Some documents are still outstanding on your side"

I think number 1 is correct