Filled Wrong Insurance Claim by Mistake and Company Approved it

Hi, Almost 8 Years ago, My father had 1 LIC Policy, and a few days back my Father recieved anothe Policy of the same Name at our address. My father presumed it as a bonus policy given by company along with 1st policy. My father keep paying premium for 1st policy for 8 years. Now this year at the time of my marriage when My father needed money he decided both the Policies to be withdraw. He filled claim in LIC for both the policies in different dates as per need. LIC approved both the policies without any question. Money Credited in Father's Account and he used all money for my marriage. Now after 4 months, LIC came back to us that 2nd Policy is not of my father's Policy. Its actual policyholder is someone else with same name and address,only 1 digit is changed in whole address. Now LIC is harrasing my father to pay back the whole money on immediate basis as its actual owner is forcing LIC for give his money back. As my father had used all money in my marriage and he doesnt have money now to pay back. Question here is if my father is liable to pay back as the whole mistake is done by LIC, 1st they couriered policy in wrong address of same name. Secondly They approved Claim without any investigation, 3rd they are harrasing my father for the mistake what he has not done intentionally. He is already a Diabetes and Hypertention patient. Kindly Guide us here what to do??