Two issues back I reported Rajesh Ganatra’s puzzle that would try Sherlock himself. A man with a roll of notes keeps moving around the store picking up goods and asks for two Vodafone top-ups amounting to £40. The retailer begins the transaction, but keeps the vouchers under the counter. The customer leaves to consult with someone in a car outside, leaves the goods, the top-ups and disappears. So does the money on the top-ups as the vouchers were almost instantly activated.

Several others have been in touch since, one reporting an almost exact enactment of Rajesh’s.

Another, Glen Hansraj, who rang from Newsflash Newsagents in Rayleigh, Essex, also lost £40 when a customer ‘left his wallet in the car’ and never came back. He got the same response that all the others got from Vodafone: try to flog the vouchers to the next customer. But in Glen’s case we reckon it was a hidden camera as the bloke had a pen in his hand. (I looked it up. You can buy a ‘high-quality’ spy pen on eBay for £7.99.)

Close-up readers will have spotted in the last issue a response from someone who pointed out that wi-fi was most likely the answer. Mate waiting in a car outside tunes into the transaction and Bob’s yer uncle.

But Rajesh got in touch again. There is no wi-fi whatsoever in his store. “That would’ve been an easy answer,” he says. “But everything is done over the phone.”

He still thinks Vodafone knows more than it is letting on. “They don’t want a big hoo-ha so are keeping schtum. They wouldn’t even talk to the Action Fraud squad.”

Any more on this subject? It is fascinating and I’d really like to get to the bottom of it.