Virgin Mobile Contract overpayment issue

Hi all,

As you all probably remember, a few weeks ago it was in the news that customers were being overcharged by their mobile phone providers. The grounds for this overcharging was that after your minimum term for example 24 months your handset should have been paid off as the price figured in the cost of the handset and that after this point technically the bill should drop as the handset was paid for and now you're only paying for usage.

Long story short, I complained to Virgin via Resolver about my contract which I have had since April 2014 which minimum contracted term ended in April 2016, a full 18 months i've been paying the full contract amount despite my handset being paid for after 24 months. I received a response in the post on Saturday stating they had reviewed my account and came up with this points... this is their exact words

"Your contract was broken down as £30 for your tariff and £11 for the handset. So in effect you have paid £11 a month extra for 18 months. As a goodwill gesture we can credit 6 months of handset payment back which is £66. This has been applied as credit to your account."

So what do you guys think? Personally in my opinion they have admitted in black and white they have over charged me £11 a month for 18 months (now 19 as they've just took Novembers bill last week) which racks up to £209. I don't think "crediting" me with 6 months is acceptable considering they've basically admitted to robbing me. They said elsewhere in the letter it's MY responsibility to contact them to cancel the contract on the 24th month, no argument there except I didn't/don't want to cancel the contract, merely have the bill reduced to reflect my actual usage.

I want my full 19 months overpayments refunded, no credited and I think a goodwill gesture should be put on top for the inconvenience, not "given" back less than a third of what they've took in a way which doesn't cost them anything anyway.

What do you guys think? How should I proceed given i've got the letter in hand of them admitting to this?

Cheers