How to ignore calls, that they can be accepted on other clients

FreePBX Configuration
2

First, try Terminate Call → Busy. I would guess that if one device reports busy, your provider will continue ringing the others.

If that doesn’t work, create an Announcement consisting of (for example) 60 seconds of silence. Set Don’t Answer Channel to Yes. Set Destination after Playback to take a voicemail, or as desired.

If that also doesn’t meet your need, see