Accidentally Connected to my Neighbor's Speaker, What to Do?
Step 1: Factory Reset & Turn OFF.
You want to Factory Reset the Transmitter Adapter AND turn it off right after it's been reset. Do NOT give it a chance to reconnect to your neighbor's device again.
Step 2: Get your Headphone/Speaker/Receiver.
Turn it on and get it into Bluetooth Pairing Mode.
For Avantree Headphones/Speakers/Receivers: The LED indicator on the headphone/speaker/receiver flashing RED & BLUE.
For Non-Avantree Products: Look it up by Brand.
Step 3: Turn on the Avantree Transmitter.
Now you may turn it on. Since your Headphone/Speaker/Receiver is closer in proximity, it should pick yours over your neighbors.
If it still somehow manages to connect to your neighbor's device... Try step 4.
Step 4: Do the Pairing Elsewhere.
Go somewhere that's not in the range of your neighbor's device and try again.
Of course, there's also the option of knocking on your neighbor's door and ask him/her to turn the device off...
Hope this helps!