Why can't I work M&S self service tills?

[Atre]

Everywhere else is fine - up to a point; obviously there's the errors in bagging area and all that shit. But with M&S it takes me ages just to get the bastard thing to scan a code at all. There's only six actual tills in ours now so didn't have much choice but to do self service and honestly it took forever, stood like a twat waving my bloody manchego at the stupid fucking red light. What am I doing wrong?

I tried the 'Scan and Go' in Sainsbury’s yesterday. Now renamed 'Scan & Stay'. Ffs even the assistant had to point her scanner at the checkout over 20 times to get it to work.

I've had issues with the M and S self-service scanners in the past,as did my DM and my DD. So it's not just you! While we're on the subject of scanners,does anyone's else have problems with the self-scanning 'shop and go' scanners in Asda? I'm fine until I get to the till to pay,but I can never ever get the hand-held scanner to scan that QR thing on the screen. I have tried every conceivable way,but no,every bastarding time I have to call an assistant over to help me,who invariably does it on the first attempt!