Date of Exit not Updated By Previous Employee

my previous employee has not update my date of exit. And when i tried to contact them i was informed that the company has changed. Anther company has taken over it. And when i tried to discuss it with that company hr he is asking for proof that i worked in that company i have company's Employee-id but not the documents. And he not ready to understand. So what should i do.
Its been three years since the company has changed. And i came to know a week ago wen i file a online claim for EPF.
Please help me.

First take steps to obtain experience letter from that company for your future employment

Dear Sagar,
Even though the company was taken over by other employer, he can have access with the PF code of the old establishment with the establishment's user name and password. If you have payslip or your Uan passbook show it as the proof.