I am trying to get a couple Yealink phones to forward to a cell phone when they are in DND mode, but it is not working for both internal nor external calls. When I turn on DND no matter what forwarding options I selected it always just goes straight to voicemail. The only way I've been able to get it to forward is by putting it on DND and using the "When Phone is Busy" Send to my mobile number. This unfortunately won't work as intended. Any suggestions? Or does DND forwarding just not work on Yealink Phones?