If incoming calls are going to voicemail before they are routed to the next device or telephone number you specified in a rule, that means the Allow calls to this number to ring for x seconds before transferring to voice mail or the next device list in Routing Calls
setting for that device is too long and must be adjusted. This setting is under your Voice and Video
-> Preferred Numbers
For example, if that setting is set to 10 seconds and your device allows only 9 seconds before it goes to the voicemail associated with it, decrease the number of seconds for the setting. Otherwise, calls will continue to go to voice mail, rather than to the next device specified in your rule.
Parent topic: Troubleshooting calls