Yamaha TW-E3C True Wireless Earbuds (Red) - Manual (Page 25)

3
With earbuds (L) and (R) turned on, long-tap the Touch Control on earbud (L) and
on earbud (R) at the same time for about three seconds, and then release your
fingers.
Flashes
3 sec
Earbud that is now primary
Either earbud (L) or (R) will be the primary earbud, and its indicator alternately flashes while
you hear the message “Pairing”.
The first Bluetooth device is temporarily disconnected in order to connect to a second
Bluetooth device. Once you’ve connected to the second device, reconnect to the first device
so that you can simultaneously connect to both devices.
25
Bluetooth® Connectivity > Connecting to two Bluetooth devices at the same time (multi-point connection)