Query on pf

I was employed in an MNC and related to job I worked outside India close to 6 years. During this 6 year company was giving me salary outside India and no PF was credited. After my outside country assignment I came back to the same company and PF was credited to the same account. After an year I joined another company - they opened a new PF account for me. I am trying to submit a claim to merge my old PF Account to my current PF account - this keep rejecting from PF office telling - they need details of NCP days and reason from previous company. Its between the previous company and PF office this claim keeps rejecting. My question is what is the correct procedure to get this claim approved ? PF office telling they may need the PF amount credited for the 6 years or need to have closed and open a new PF account from the old employer. They keep telling there is a file they maintaining for these sort of employees from the company and they keep rejecting this - as company didn't follow the rules.