Any PPI will need to go back to your creditors. We have had a couple of posters speak of this company - if they have cold called you, I'd avoid them. How do they know your details?
Sharing from experiences of dealing with debt
The greatness of a man is not in how much wealth he acquires, but in his integrity and his ability to affect those around him positively.
Bob Marley. http://kallis3.blogs.iva.co.uk
If you never directly contacted this company then just throw any paperwork in the bin, they have trawled the IR and found your name and address and are just trying their luck that there maybe additional PPI they can claim in your name and rake the ~40% commission. That ~40% would legally be payable to your IVA company and you would have to find it from your income, it's a loophole, but ultimately it is a scam.
Last Payment made 04/12/14. Completion Certificate 25/7/15. IVA company GT. No Issues
They are being a bit "inventive" with the facts. If you have or had an IVA, PPI is rightly payable to the creditors as recently ratified in court. IF, after the IVA completes, the IP declares that he has no interest ( a rare occurrence) any PPI still due to be claimed could be yours.