As the above have mentioned, to get a refund of PPI you need to have been mis-sold (as in; weren't told it was being added, told you had to take it to get the loan, sold it when you already have similar insurance, were self employed etc)
If the above don't apply to you and you just genuinelky took it out as you wanted it, never made a claim and now just want a refund, technically you wouldn't be entitled to a refund, but a lot of companies see it as more cost effective to refund, than to fully investigate each case.
If you've claimed against the policy, i don't think you can get a r