You may lose the connection with the subwoofer because of below given reasons:
1. The subwoofer and the soundbar are not in the same room.
2. The distance between the soundbar and the subwoofer should be not more than 3 meters (9.8 feet).
3. There is an obstruction between the soundbar and the subwoofer, such as a couch or table, etc.
4. There is no low frequency information in the content being played. In this case check if the LED at the back of the subwoofer is solid.
If the LED on the back of the subwoofer is blinking, the subwoofer is in pairing mode. Wait for the soundbar and the subwoofer to get paired.

If the subwoofer LED is not blinking and is not solid, try below given steps:
1. Make sure the soundbar and wireless subwoofer are properly connected to the power supply.
2. Press and hold PAIR at the back of the wireless subwoofer until the blue LED on the subwoofer flashes quickly. The wireless subwoofer is ready to pair.
3. Press on the top panel of your soundbar main unit or the remote control to power on your soundbar main unit. The soundbar and wireless subwoofer will pair automatically. Pairing is successful. The blue LED remains on solidly.