Try these steps to resolve your issue:
Cannot pair speaker with Bluetooth® device
Applies to:
Make sure Bluetooth is turned on or enabled on your device
Make sure you select “Bose Mini SoundLink” in you device's pairing list and that the connection is confirmed by your device
Your Bluetooth device may be out of range. Try moving it closer to the speaker
If possible, turn off all other nearby Bluetooth devices or disable their Bluetooth functionality
Make sure your Bluetooth device supports the A2DP (stereo Bluetooth) profile
When connecting to a PC or Mac computer, make sure to select the Bose® SoundLink® Mini speaker as the audio output device within the audio settings menu of the device. You may need to play an audio track to finalize the connection (see the device manufacturer for detailed instructions)
Check for updated software for your Bluetooth device, or go to owners.Bose.com for updates to the Bose® SoundLink® Mini speaker