To get the updated permissions, reboot or just unplug and replug the barcode scanner. This was tested on a Raspberry Pi Zero W running Rasbian Stretch Lite. USB interface was using a USB-OTG cable.
RETSOL LS 450 Laser Barcode Scanner BIS Approved Handheld 1D USB Wired Barcode Reader Optical Laser High Speed for POS System Supermarket Here’s a high performance barcode reader that gives ...