I’ve banked with Nationwide building society for more than 30 years without a problem – until last week when it blocked my debit card without explanation.

I’ve spoken to four members of its fraud team. They have been helpful and kind but their suggestions have, sadly, not resolved the matter. I am running out of money and have had to cancel a Sainsbury’s food delivery because I can’t pay for it and will soon be out of food.

Can you please help?

JR, Uxbridge

We have received a few letters from readers in recent weeks complaining that their Nationwide accounts have been frozen. However, in this case, the move appears to be justified.

When I spoke to you it emerged that you had been trying to buy an iPad for a grandchild and had made 15 attempts to buy one online at various retailers after failing the verification process each time.

It blocked payments on the basis that this was not the kind of purchase you typically make, and fraudsters very much do. And it tells me that you had frozen your debit card yourself via its app, possibly fearing that you were about to be defrauded.

Happily, all is resolved and your account is fully up and running again.

Nationwide says: “We apologise for the inconvenience caused as our customer was purchasing an iPad, although this was done to protect him. A potential fraud alert was raised which led to the blocking of the transaction.

“The customer had also frozen his card via the mobile app, which meant he was unable to make any purchases.

“Once we spoke to the customer, we were able to remove the restriction and help unfreeze his card. Unfortunately, our customer’s calls were cut short while he was on hold, and we will be offering a compensatory payment as an apology.”

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