A mother says she was left unable to pay the bills after  a mix-up while paying for petrol at the pump.

Harriet Welsh, aged 36, filled up her car at the Westhoughton Sainsbury's petrol station on January 24. 

Harriet, who now lives in Standish but resided in Westhoughton until recently, used the pay-at-pump function and put £10 of fuel in. 

The Sainsbury's website says self-service pumps require a £100 pre-authorisation amount before starting the fuelling process. 

It states when the transaction has completed, it will send the true amount to a customer's bank, with the pre-authorisation amount being "almost immediately released back to the customer's account". 

However, Harriet said the £100 remained in pending transactions for over two days. 

Her bank says the the supermarket incorrectly processed the fuel transaction as a standard groceries purchase, rather than a pay-at-pump transaction.

Sainsbury's say it is investigating.

The amount has now been paid back into her account. 

The Bolton News: Sainsbury's Petrol Station in WesthoughtonSainsbury's Petrol Station in Westhoughton (Image: Google Maps)

Harriet claims that this prevented her from paying her mortgage and for her daughter's baby milk. 

She said: "It was in the pending but I had less than I needed. If my partner hadn't lent me the money I would have been struggling. 

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She says that she will be paying at kiosk from now on.

Harriet said: "Then Nationwide and Sainsbury's were going backwards and forwards. If the money was in, it would be gaining interest, something which I also need. 

"If they take that money and hold it, I should have got it back immediately but it never did that." 

Harriet added: "I just want to make people aware of it. It could have been an old lady on a pension, who might not be able to pay their bills either. 

The Bolton News: Harriet WelshHarriet Welsh (Image: Public)

" I have also had to spend extra time getting it sorted, I have got my daughter to look after as well, time I couldn't afford to lose. 

"It has come back in now, I did get compensation from Nationwide, but I think Sainsbury's should accept responsibility, the contract is with the merchant, they are the ones who have taken the money out." 

A Sainsbury’s spokesperson said: "We are investigating this customer's unusual experience and we are very sorry for the inconvenience this has caused.” 

A Nationwide Building Society spokesperson said: “We appreciate the frustrating situation our customer found themselves in. In this case, the supermarket incorrectly processed the fuel transaction as a standard groceries purchase, rather than a pay-at-pump transaction.

"Unfortunately, this resulted in the fuel purchase transaction not matching to the reservation, resulting in both values appearing on the customer’s account. 

"This would not have happened had the original reservation been processed correctly.”