Questions of Cash: I had a devil of a time over my double payments to Demon

Q. I made a duplicate payment to Demon Internet, after it debited my account with a charge for two invoices that I had already paid by cheque. When I pointed this out to Demon, it demanded proof of payment.

I was astonished in September to receive a phone call asking me to provide photographs of both sides of my cheque, or else details of the sort code and account number of the account into which the money had been paid. I pointed out this was unreasonable, but agreed to obtain a copy of the cheque – which I have now received. The bank tells me that for data protection reasons it is unable to tell me into which account the money was paid. To put it politely, this is very poor customer service and it seems that the company's accounting system is hopelessly inadequate. I am owed a refund of £36.74. DB, by email.

A. Demon Internet is a subsidiary of Vodafone. Your cheque was made payable to Vodafone, to whom you sent the cheque. This seems to have caused problems, even though the cheque was accepted by Vodafone and paid into one of its accounts.

A spokeswoman for Vodafone apologises and explains: "The credit card payment failed initially and although it seems that [the reader] sent us a cheque for the outstanding payment, this was addressed to the Vodafone Newbury HQ rather than to the Demon PO box address in Glasgow, and the money is in a different account. Meanwhile, we successfully took the payment from his credit card. We have apologised to [the reader] and reimbursed the overpayment. We are working to make sure this doesn't happen again."

An unrewarding time with credit card bills

Q. I inadvertently joined Rewards.com in December 2012 when I ticked a box to get £10 off the cost of an online purchase. Rewards.com then offered me money off various products like events and meals out. I received a letter from the company which advised me that it would start charging for membership after a month's free trial. I immediately cancelled my membership by return email on December 17.

I only realised in June this year, when checking my credit card bill, that Rewards.com was still taking £10 a month from my card account. I immediately contacted them by phone, spoke to various people and eventually was promised by a manager that the account would be cancelled. I also spoke to my credit card issuer, Marks & Spencer, and agreed with them that the June payment would be cancelled and no further payments processed. But £10 was again taken on my next three credit card bills. I don't know what to do now other than cancel my credit card. CB, by email.

A. It took us several weeks and numerous emails to establish that it was two other rewards schemes – Let's Go Rewards and Complete Savings – that you joined. These schemes are entirely separate and unrelated to Rewards.com. As far as we know, you did not join Rewards.com – though this proved impossible to check as only registered members or scheme applicants are able to access the Rewards.com website, or have their phone calls accepted. Your charges from both Let's Go Rewards and Complete Savings have now been refunded.

A spokesman for Let's Go Rewards said: "[The reader] joined two separately administered online reward programmes, Complete Savings and Let's Go Rewards. Aimed at regular online shoppers, they provide access to discounts and cashback with major online retailers and on leisure and entertainment activities. For both programmes she would have manually created memberships by entering her name, email address, postal address and her payment card details as well as creating and verifying a password to join each programme.

Both programmes have a 30-day free trial period, after which people can remain a member for £10 per month. This monthly fee is clearly displayed in a number of places on the joining pages, including directly above the field where card details are entered. During the 30-day free trial periods [the reader] requested the cancellation of her Let's Go Rewards membership, but not that of Complete Savings. [The reader] recently contacted us to cancel her Complete Savings membership and we are happy to confirm that we have provided a full refund for the duration of her membership as a gesture of goodwill."

It took us a while to track down information on the loyalty schemes, so by this time we had already contacted Marks and Spencer, which refunded the fees on a chargeback basis. A spokeswoman for Marks and Spencer says it will monitor your account to ensure that no more related charges are processed. Your experience is a reminder of the importance of regularly checking credit card statements and bank accounts.

Laptop 'solutions' that went all wrong

Q. I bought a laptopand then had terrible problems with it. Soon after, I was contacted by phone by a company called Database Technologies, which seemed to be aware of my problems and promised to sort them out for me. But when I took the laptop back to the retailer I was told that instead of solving the problems, it had made the problems much worse. I am now receiving payment demands from Database Technologies. The police have told me to ignore the bills, but now I am being contacted by a debt collector. MG, London.

A. We emailed both Database Technologies and its debt collector explaining that your laptop problems had been made worse by their "solutions" and so their service had been of no value. We added that online checks revealed other customers had expressed unhappiness about the company.

We stated that in the light of this we would like confirmation that the debt had been written off and that no further action would be taken in terms of either debt collection action or an adverse credit entry. We had no reply to this, or to our reminder email. Hopefully you will have no further correspondence from this company, but if you do please pass it on to us.

Questions of Cash cannot give individual advice. But we'll do our best to help if you have a financial dilemma. Email us at: questionsofcash@independent.co.uk