Solutions:
1. Put the single earphone into the charging box, long press the function button for 2 seconds, and use device A to search and connect the earphone.
2. Take the single earphone connected to device A out of the charging box, put it into the other earphone, long press the function button for 2 seconds, search and connect the earphone with device B, and then connect the two single earphones to different devices.
Note:
Clear the connection record of the two unilateral earphones before using this feature.