One scanner, two jobs. The switch is at the top of the screen and it changes what a scan does, not just what it looks for.
The two modes
They are separate on purpose. Someone can walk in at six and eat at eight, and neither should consume the other.
Reading the screen
The mode bar always states what the current mode does in a full sentence — "Checking people in · no meal coupon is used by these scans", or "Collecting meal coupons · nobody is checked in by these scans". If you are unsure which mode you are in, read that line rather than the highlight.
The aiming frame is tinted differently per mode, and the green verdict changes wording: "Let them in" in ENTRY, "Give the meal" in FOOD.
The mode sticks
Your choice is remembered on that phone, per event. A phone stationed at a food counter stays in FOOD mode across restarts, which is what you want — but it also means a phone handed from the door to the counter arrives in the wrong mode.
Check the mode when you take over a phone
The most common mistake at a multi-station event is a phone that changed job without changing mode. Ten seconds of reading the mode bar at handover saves a queue.
"Wrong scanner mode"
Scanning an entry ticket at a food counter, or a meal coupon at a door, produces a violet Wrong scanner mode verdict.
Nothing was recorded, and nobody did anything wrong
This is the scanner telling you it is in the wrong mode. It is deliberately not shown as a refusal: the attendee's code is perfectly valid, and treating an operator's mode mistake as a bad ticket would accuse somebody of forgery in front of a queue.
Switch the mode at the top, then scan again.
If FOOD mode shows nothing
A screen saying "No meal coupons on this device" means either the list needs re-downloading, or this event has no meal-bearing ticket types at all. It offers both a re-download and a way back to ENTRY.
Only ticket types the organizer marked as including a meal generate coupons.
Next: What each scan verdict means about what each scan verdict means.