My question involves a child custody case from the State of: GA

I know that I have to file legitimization papers but twice when I took them up to court I was directed by two different people to do two different things, and now I'm lost with what to do. The child of the mother and I signed over our rights to give the maternal grandmother temporary legal guardianship when she was three months old (in 2006) because neither of us could financially or physically care for her at the time. The mother of the child lives somewhere in Lilburn, the information has been withheld from me and the maternal grandmother recently moved to Loganville, also address has been kept from me. I went to file in Rockdale County because that is where the child lived at the time of placing the guardianship but they told me that I would have to file and serve where the mother lived. Even though the woman I spoke with the week before had been willing to accept my paperwork and serve the mother but I did not have the correct amount of money at the time.

The guardianship papers say that the maternal grandmother is supposed to let the court know with any address change but am unsure if they have let the courts know but am open to going by the courthouse and asking if they are aware of this change. However, I just feel confused... do I file the legit papers in the court that knows the case or in the county that the mother lives or where the maternal grandmother/legal guardian lives?