Diagnosis
The soundbar's Bluetooth is not in discoverable mode. It only stays discoverable for 3 minutes after activation. An existing paired device may also be blocking new connections.
How to Fix It
Put the soundbar in Bluetooth pairing mode. On the remote, press the 'Source' button until 'BT' appears on the display. Then press and hold the 'Play/Pause' button on the remote for 3 seconds. 'BT PAIRING' will flash. Now search on your phone.
If That Didn't Work
Clear the old Bluetooth pairing list. With the soundbar on, press and hold the 'Volume Down' and 'Gear' buttons on the remote simultaneously for 5 seconds. The display will show 'BT LIST CLEAR'. Then try pairing again.
Heads Up
Bluetooth range is about 33 feet without obstructions. Move your phone closer. Also, the B650 uses Bluetooth 4.2. Some connectivity issues with newer phones are due to power-saving features on the phone, not the soundbar.