Two i-130 forms were submitted of one person

[m92razi]

I and my younger sister I-130 were submitted in January 2011, later they were closed coz of non response of the letters they sent us and we did not get. Later after appeal, the case were reopened for me and my sister but unfortunately my younger who is petitioner applied again in 2013 March, i guess, for my other younger sister whose I-130 form was submitted alongwith me in 2011. Now when the case were reopened the, USCIS office gave me my priority date from January 2011 but for my younger sister, they have given 2013 date of priority. We actually want to request the office accept the previous application and discard the second application submitted in 2013 for my sister. How we can do that and what steps should we take to do that.. Unfortunately we misplaced every detail of the previous case and when we call USCIS call center they only see two case that is mine with priority date 2011 and my sister's 2013. We told them that there was a previous case but they are not of a good help. One of the agent confirmed me while I was talking to him that my sister's two cases he could see, he also said that we were lucky that we could go back to the previous case. Now my sister who is a petitioner has been informed that they only got one application for my other sister who is applicant. Please help how we can get it done.. Thankx..