Each transponder has a unique identifier which is a combination of letters and numbers. This identifier needs to be mapped with the correct bib number of the participant in RACE RESULT 12. To assign all chips to participants, import your chip file in the Timing tab, under Settings > Chip File.
Make sure to do that before you receive any detections, otherwise the reads may come up as UNKNOWN or create participants with a random bib such as 50001.