If you're one of the two million flogged worthless card protection by Affinion (often branded Sentinel), you should have received a letter informing you about a redress scheme. If you haven't had one and think you're affected, call the scheme now.

You may be entitled to £100s back if you got Affinion/Sentinel card protection either directly, via a bank such as Barclays, HSBC, Lloyds, RBS and Santander, or from a card provider.

See our Sentinel (AI Scheme) card protection guide for full step-by-step help to reclaim your money.

The problem is that the 'card security' part of some of these products, which covered fraudulent use if a card was lost or stolen, was completely unnecessary as card issuers are typically responsible for fraudulent transactions.

Letters were sent out between 27 January and 23 February 2015 to those affected telling them that a redress scheme called 'AI Scheme' had been set up by regulator, the Financial Conduct Authority.

Sentinel told customers to allow a week for letters to arrive by, but as this deadline has long passed, if you've not received one and think you should have, call the Al Scheme on 0800 678 1930. It may be that it's got the wrong address for you.

I've got the letter. Do I need to do anything?

You don't need to do anything when you get this first letter. It just explains that you may be entitled to redress. You'll then be sent another letter by mid-May 2015 to vote for the scheme, then another to claim for compensation, if the scheme gets the go-ahead.

It's crucial to be aware that these aren't spam, or in any way related to PPI or other types of reclaiming. Some readers have already told us they may have wrongly binned their letter.

As Paul tweeted: "Knew not to bin AI letter thanks to @MoneySavingExp. Could be in line for £160 compensation + interest #fingerscrossed."

All letters sent will be branded the same, so familiarise yourself with them (see the example below), so you don't accidentally chuck them away thinking they're junk mail, as many did with the similar CPP redress scheme.

How much could I reclaim?

The scheme covers policies sold between 14 January 2005 and August 2013.

If the scheme goes ahead – it first needs to be voted for by customers and then approved by the High Court – those mis-sold will get back every penny paid for this cover, which usually cost £25/year.

You'll also get interest, which is calculated at 8% per year, but you do not get interest on the interest (ie, it's not compound interest).

However, if you've made a claim, the value of any claim will be deducted from the redress. If your policy is still active and you decide to claim for redress, your policy will be cancelled.