One earbud won't connect or power on | Bose Ultra Open Earbuds
Check if the battery is charged.
Be sure the battery is not depleted. For more info see, Checking the remaining battery charge and Charging your headphones.
Reset your product.
Much like rebooting a smartphone, your product might need to be reset on occasion to correct minor issues. For more information, see Resetting your product.
Reboot the Bluetooth device.
Electronics, such as cell phones, tablets or computers, might need to be reset on occasion to correct minor issues. This is typically done by shutting down the device, then powering it on again.
Try connecting a different Bluetooth device.
If your earbuds connect to another Bluetooth device, it suggests that their Bluetooth is working properly. The issue may be with the first device or its settings.
