Cashback app Shopitize has suspended a number of its users' accounts as part of a crackdown on potential "fraudulent activity" – leaving many insisting they've been wrongly targeted and one user claiming he's lost access to £600 of cashback intended to fund his family Christmas.

The Shopitize app lets shoppers earn cashback on spending at stores such as Boots, Asda and Greggs by photographing barcodes of items and receipts. It claims to have over 100,000 users.

However, it appears customers who have logged in to the app on the same mobile phone as fellow users have come under suspicion for "fraudulent activity", with dozens complaining online of being locked out of their accounts since the end of last week and several contacting MoneySavingExpert.com directly.

Shopitize told us its system had "picked up some potential abusive activities on user account(s)... therefore the system has suspended account(s) pending further investigation."

In an email seen by MSE, which was sent to multiple users, Shopitize said "accounts that are linked to multiple other accounts" have been deactivated where the number of connected accounts is "above the level we deem to be fraudulent".

It's not clear exactly what fraudulent activity is suspected to have taken place, but different Shopitize users are shown different cashback offers, and Shopitize forbids users from having more than one account.

Martin Lewis
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How does Shopitize work?

With the Shopitize app you have access to cashback offers on particular products – such as 40p cashback on a particular brand of bread (though as above, different users will see different offers). You browse offers and unlock them by selecting them, having completed an action such as answering a survey.

Once you've bought the item, you scan its barcode in the app and then photograph and submit the receipt. Shopitize verifies the purchase and you get your cashback.

What are customers saying?

One customer we've spoken to, who asked not to be named, told us she and five other members of her family found that they couldn't log in to the app late last week.

On contacting Shopitize, she received an email saying her account had been deactivated because she was suspected of "abusive activity" on the app. However, she insists her family hasn't done anything wrong.

Though she admits she sometimes logs in to the app from her husband's handset, and her son sometimes logs in from hers, she says they all use their own individual accounts with separate login details.

She explained some family members had better smartphones than others, making it easier to scan barcodes and upload receipts in the app. She said this was why they tended to share handsets when using the app.

Another customer, Peter Rigby, told us: "I, like many others, encouraged my family to use Shopitize as a way of saving for holidays and Christmas.

"The savings were coming along nicely for this Christmas – about £600 collectively. Then without any prior warning, we find our accounts have been blocked and our funds frozen."

Peter says he has no idea what he's done to prompt the action: "I have emailed Shopitize and asked them to explain exactly what it is we are all accused of."

Dozens of affected customers have posted complaints on the app's Facebook page, a thread on the HotUKDeals website and social media. One said: "I'm waiting for an apology still from Shopitize for that email that was sent to me! Not bothered about the credit in my account – I just want a public apology."

Users of cashback app Shopitize furious after being locked out of 'linked' accounts
The Shopitize app lets shoppers earn cashback on spending at stores such as Boots, Asda and Greggs

What does Shopitize say has happened?

We've made repeated attempts to speak to Shopitize in recent days. Though the company is yet to answer our specific questions, we did receive this email from it:

As per our terms and conditions we retain the right to suspend, and ultimately cancel, accounts of users where we believe that an abuse of Shopitize services has occurred.

We conduct regular reviews and in a number of cases, our system has picked up some potential abusive activities on user account(s). As a result, therefore the system has suspended account(s) pending further investigation.

We understand that in some cases friends or family members may share a communal device when using Shopitize and we have taken this into consideration. The suspended account you are referring to... [is] connected to a number of other accounts that is above the level we deem to be reasonable or acceptable and therefore unfortunately the accounts have been suspended.

We are currently looking further into individual cases and the underlying activity. This process may take some time but we will be in contact with individual users as soon as possible to inform them of our final decision.

We will not comment on any individual case unless you are the account holder.

What are Shopitize's rules on multiple accounts?

Shopitize's FAQs state: "Every shopper can have only one account. If you do have more than one account, may we ask you to keep only one of them, or we may have to delete all of them in order to provide our service fairly to all our users."

The app's terms and conditions also clearly state that: "Any suspected fraudulent, abusive or illegal activity... may be grounds for termination of your use of service."

However, when we checked the site and the T&Cs it wasn't immediately apparent whether multiple users are allowed to use Shopitize on the same device. We've asked Shopitize this and will update this story when we know more.

I've been affected – what can I do?

If you believe your account has been unfairly frozen, you can try to contact Shopitize via its online form or by emailing feedback@shopitize.com.

Are cashback sites and apps safe?

Cashback sites and apps can be a great way to make a bit of extra money once you've found the perfect deal. But as our cashback safety rules make clear, you should always withdraw cashback as soon as you can. Never store it in the cashback site, as if the company goes bust you could lose it all.

Some won't let you withdraw funds until you reach a certain level – with Shopitize, it's £4.

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