When scanning items during picking, bundles behave differently from regular multi-item orders:
Bundle (e.g. accessory + main product): scan the accessory + the package only - not every component separately.
Non-bundle, multiple items: all items must be scanned individually.
A product is treated as a bundle only when it has the linking properties tying its components together.
If a bundle isn't scanning as expected, its components may be missing their linking properties - contact support and we'll check the setup.