The Airwires DRC confirms this is a physical PCB routing issue: the schematic net exists, but the PCB pads are not connected by copper. I re-ran the check and Flux still reports 3 Airwire errors, so route Net 2 between D1:A and R1:P2; after routing, re-run the Airwires review to confirm it clears. The remediation guidance is to fix airwires by routing the affected net, then re-validating with the Airwires review .