An NS&I customer has reached out to the provider after their suspicions were raised as they tried to log in to their account.

The individual got in touch over X to ask: “If you insist on 2FA [two factor authorisation] to log in online, why don’t you make phone number a mandatory field when registering?

“I’ve just registered, tried to log in, been told I need to ring you to get a number added, rang, fought the virtual assistant, got put through to someone who was on a terrible phone line, who then said their system crashed and asked for a different two letters of my password (which seems dodgy).”

The provider responded to explain how the login system works. They said: “I will forwarded your comment above as feedback to be looked into further.

“When authenticating a customer on the phone, we need to ask for two digits of the password. The agent does not know what the password is and is given two blank boxes to enter the digits.”

The customer further explained when their suspicions were raised. They said: “It’s when I give two digits, then get told the system crashed and they ask for a different set of two digits that things get fishy.”

But the savings giant reassured them this was the proper procedure. The representative said: “If there is an error with the system which fails the attempt or the characters are incorrect, the system does ask for two different characters instead.

“You only get five chances to log in until the system suspends the password.”

A Premium Bonds holder recently contacted NS&I as their £125 winnings had still not arrived in their bank account a week after the prize draw.

They asked over X: “I topped up my Bonds to £50,000 last month (the new ones weren’t in the April draw though).

“Also changed from reinvest to pay out. I won £125 but it’s not been paid out. I either now have £50,125 Bonds or you need to pay out the £125. When do the prizes get paid?”

The group replied: “Premium Bonds prize winnings are paid by the seventh working day of the month. This month the seventh working day is the 10 April.”

A customer can hold up to £50,000 in Premium Bonds – buying more Bonds increases your chances of winning a prize in the monthly draw.

The draw includes two jackpot prizes for £1million and other big winnings of £100,000 and £50,000. A person can win several prizes in a single draw.

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