Last month, my 84-year-old mother spotted a £47.56 charge from a company called On Top Up on her credit card bill that she did not recognise.

When I looked into this, it emerged she had been unintentionally subscribed to a monthly mobile top-up service since September 2021 and had paid the firm just over £1,900.

It dates back to when she asked her grandson to add a one-off top-up of £40 to her pay-as-you-go mobile. I assume that he Googled it and landed on a sponsored link for this firm, which charges a fee for the top-up mechanism – so a £40 top-up cost my mother £47.56.

Based on the company’s Trustpilot reviews, she is not the first person this has happened to. The mechanism to activate the top-up appears to involve an ambiguous step that can result in a customer unwittingly triggering a monthly subscription.

On Top Up doesn’t notify you when the monthly vouchers are issued. They just sit in an online account – in this case, in her grandson’s. Neither does it send alerts to say they haven’t been activated or expire after two months.

Initially the company offered to refund one month but, after we escalated the complaint, it has increased this to a year. I think my mother should be entitled to all her money back.

SD, by email

Your mother’s experience of inadvertently being signed up for monthly top-ups is echoed by other customers in the negative reviews that contribute to the firm’s “poor” Trustpilot score.

On Top Up pitches itself as a “simple way” to add credit to any mobile phone on any network, but it is a broker and its credits attract a hefty near-20% mark-up, starting at 95p for a £5 top-up.

You got On Top Up to increase the refund on offer several times (its standard policy is four months) but in the end threatened a small claims court action. It then offered £1,440 – she had already received £190 from her credit card company, so this is the money back for the top-ups, less the fees – but you felt it was dragging its feet in transferring the money. After a nudge from me, however, it has arrived in your mother’s account.

On Top Up says: “Recurring charges only take place if the registered user manually activates the auto top-up feature from their account.” Customers can access their account on its website to turn it off if they wish, it says, adding that your mother’s refund was a “non-obligatory gesture of goodwill”.

It is easy to click on the first web link you are presented with when rushing to top-up, and this shows this can result in an expensive error. But a service should not be set up in a way that so readily trips people up.

You May Also Like

My boyfriend wants us to move in together – but I need my independence and his dog won’t let us have sex

My boyfriend and I are in our late 50s. He never married…

I no longer have any sexual desire – and now my husband is talking about a threesome

I have been married for three years and no longer have any…

‘My mother-in-law has upset me greatly. Should I seek an apology?’ | Ask Annalisa Barbieri

I’ve had a terrible run in with my mother-in-law and don’t know…

This is how we do it: ‘After mutual cancer diagnoses we didn’t have sex for five years. Then we discovered toys …’

Jill, 76 If it hadn’t been for walking the dog, we would…