Note : There is a button inside the charging case.

•  Make sure your earbuds are fully charged.
• Delete/remove the Noise Buds Xero from the paired devices section in the BT menu.
• Insert both earbuds into the charging case with the lid open. Press the charging case button for 10 seconds.
• The white LED on the case will start blinking, this indicates that the earbuds have been reset."