Ivl Finance Ltd — Someone else's loan account attributed to me and wrong non payment reported to Experian.

I was shocked to see that my credit score on Experian had gone down by almost 150 points. I have never ever defaulted in my payments. On checking the details, I found a non payment attributed to me by IVL Finance Ltd. On checking the details, I found that my Pan number is mentioned on that loan account but the two address of the loan receipent are in Tamil Nadu and Andhra Pradesh. The date of birth as well as phone number is also different. There seems to be some wrong entry by them regarding pan number or someone has wrongly used my Pan Card. In either case it is the company's fault because they have not verified the details. Please help me