Zinc Recoveries Specific Situation

A question about : Zinc Recoveries Specific Situation

I've been looking through a few posts with dealings with this Debt Collection agency Zinc Recoveries but I thought I'd post up my specific dealings with them:

My father paid for the internet broadband costs with a credit card, which started years ago. The company Nildram got swallowed up by Opal and then Talk Talk Business.
TalkTalk often phoned me up asking to go on their residential service with their phone line etc, (i'm with them now on a residential contract, but at this time I ignored that and let it stick with my father's credit card.)
When my dad tried to change over to pay with his debit card, they sent him to residential and twisted what he wanted into changing to their phone line.
I saw this after a letter came in from BT saying sorry to see you go etc, and phoned up TalkTalk to cancel everything. Later I phoned TalkTalk to confirm the cancellation, the internet then went offline as expected.
3 months later, my father's credit card is getting billed for 3 months of internet service on TalkTalk Business we never had.
I explain we cancelled this and didn't receive the product. The manager on the other end says this is TalkTalk business, we have nothing to do with residential. I explain that my info was clearly in the hands of both from their relationship and that they knew enough to cancel the internet on those specific dates and the bottom line is I didn't receive the product those months as the internet went offline as expected.
I put up a retail dispute with the credit card company. I also phoned TalkTalk Business and another employee agreed that with all the confusion, my explanation that I didn't receive the product and with the marginal costs, they would put up a credit notice and have the charges dropped. I rung later to confirm this went through. The charges on the credit card dropped to less than Ј2 and my father paid it.

Now a month later (after I think all sorted) they are sending me letters, asking for payment for Ј16 and also a letter from Zinc Recoveries on their behalf wanting Ј81. The charges they claimed I owed was only Ј61 anyway, so this is inconsistent.
What should I do now? Ignore them both?

Best answers:

• Ignore the DCA, write to talk talk customer complaints, tell them the story and ask why you are been hounded now for the extra cash, and why have they instructed a DCA to contact you ? only they can answer that, see what comes back, and take it from there.
• If at all possible, do this in writing, even via email, so you have a paper trail of what happens, and preferably written confirmation of the cancellation of the contract and associated debt.