in detect people only person 1 appears not the others that are in the photo

Initial troubleshooting:

1. Please do the LR menu command Help > System Info and copy/paste the entire contents here so we can see exactly which versions of hardware and software LR thinks you're running.

2. Upload the photo to Dropbox, Google Drive, or similar and post the sharing link here. We can see if this issue occurs on other LR installations with that photo or it's specific to your installation.