United Bank Of India [UBI] — loan sanctioned to other customer using my pan details

Recently i visited bank for loan but my loan was not approve as they say i already have an agricultural loan which was sanctioned in the year 2005 from united bank of India.so i check with the branch on this as i have not applied for any such loan and even my pan card got issued in the year 2014.
The manager told me that he have checked the file and he found out that the loan taken by the person name and my name is same but other details are different like fathers name and address..so it proves that i haven't taken the loan but the manager is not able to answer how my pan card was used to get that loan.
what shall i do to get out of this problem.