Two forms and CurrencyMenager problem

Question

I have two forms. In first i have method witch return a ID of person. It looks like that: public int fnGetID() { int ID=0; int tempCM=cm.Position; DataTable dt=fnFillDataTable(); ID=Convert.ToInt32(dt.Rows[tempCM]["ID"]); return ID; }//fnGetID() when iam using this method in first form it working OK. But when iam run this function from form2 like this Form1 f1=new Form1(); f1.fnGetID(); it always return first row from DataTable? Currency menager doesnt refresh the position metod, why?