This dummy device may have been designed to prevent the customer from carrying out a transaction and to hold onto the customer’s card.
In such a case, the scam is likely to be executed when the customer goes inside the branch to query what has happened, enabling the perpetrator, who may be nearby, to use the device to retrieve the customer’s card, which can then be used to make ‘contactless payments’ for goods or for identity theft purposes.
Police advice is have a good look at the ATM to see if it’s been tampered with. If something doesn’t look right with the ATM, don’t use it. Report it to police on 101. In an emergency, always contact police on 999. Also inform your branch when it is safe to do so.