My dad, who handled all my parents’ financial transactions, died this year and my 82-year-old mum has been learning how to do her grocery shopping online.

She was just getting the hang of it when one-time passcodes (OTP) were introduced on her Sainsbury’s food deliveries.

The first time, we had to phone her card provider, M&S Bank, to update her mobile number so she could receive the passcodes (she hardly ever uses her mobile).

Then, today, she phoned me in tears because she had pressed the wrong button, entered the wrong code, and her card was locked.

When she finally got through to M&S (navigating the call options, in itself, was a challenge) the customer service adviser said they couldn’t unlock the card and would have to send out a new one.

The alternative to using an OTP is for her to confirm payments via the M&S banking app, or with a card reader, but that looks even more complicated.

I understand the need for security, but how can banks make it so difficult?

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CB, Wolverhampton

The anti-fraud rules, which came in to effect this year, are designed to make online transactions safer for consumers but the extra layer of security can be difficult to navigate.

M&S Bank says it proactively contacted customers to explain new identity checks and says customers who are struggling with two-factor authentication should contact it to discuss their individual needs.

M&S has been in touch with your mother and given her a specific number to call if she experiences further difficulties. You have power of attorney over her affairs and could go through this rigmarole for her. However, she is keen to maintain her independence.

Nonetheless, one way round this would be to get a card linked to her account.

We’d like to hear from readers who struggle (or help someone who does) with technology, and have found a bank or credit card company they’d recommend.

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