I have synced via Bluetooth my landline and my iPhone. The problem is when I'm out of Bluetooth range and someone phones me on my mobile only the landline can be heard, the call goes to the landlines voicemail and I never hear it until I get home and see the voicemail is played I also have the call in my iPhone 'mixed calls. I also wear a cellular Apple watch 4. My question is when a call to my mobile diverts to my iPhone is it because my Apple watch is interfering to stop my iPhone ringing when the 2 phones are synced? I have no diverts on my iPhone so I can only put it down to my Apple Watch.