I was arrested for shoplifting, when I enterred Tesco, used…

I was arrested for shoplifting, when I enterred Tesco, used the Handheld Scanner to purchase my items. I asked for meat from the meat counter, put it to one side of my trolley as I wanted to compare with the pre-packed on going to the pre-packed section chose another item and then scanned my items and placed in bags - continued shopping - and scanning with held hand device. When I got to Bread counter the scanner would not scan 2 loaves of bread I decided it could be a fault and proceeded to customer services, however half way up bread aisle in route tried scanner on different brand and it worked, so deemed it a barcode issue not machine. Continued around. Went to counter put scanner through payment machine and paid for items using debit card. Did not look at bill and continued home. Following day I was arrested for theft of meat, as 3 items of meat had not scanned? also I noticed that bags I had scanned were also not in receipt. There was no intention on my part as clearly I pay for my items that I purchase, however for some reason the hand held scanner did not work properly and now I am being investigated for theft. There is CCTV however there is no dishonesty and no intention on my behalf - the cctv just shows me shopping as per my account. The case is going to CPS for a decision, however I am at a loss as I did not steal anything and was ignorant to the scanning issues until I was arrested. It is a mistake, please advise.