Sainsbury’s, SE19 circa 2019.

There is confusion at the self check-outs.

(No surprises there).

A weary assistant raps out an instruction to an elderly customer:

‘Give me your cardigan!’

I am intrigued.

For it is a hot day and the customer is not wearing a cardigan.

The customer, however, is unfazed.

She dips into her purse and hands over her card

Again.