Call Forwarding can be enabled when your phone is Busy, Unanswered or Unreachable. To see the status of call forwarding and enable/disable it on LG G2 do as follows:
1. Open Settings and go to Networks tab
2. Tap Call (You may also reach this setting by going to Phone > Menu Button > Call Settings)
3. Under Incoming Call settings, open Call Forwarding
4. Under Forward If, select when to forward your call (Busy, Unanswered, Unreachable, or Always forward calls)
5. Now, you are asked to enter the number to forward the calls to
6. Hit Enable button and you are all set
7. to disable call forwarding on LG G2, you just need to go to Call Forwarding settings, open the selected forwarding option, and tap the Disable button
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