Sorry for facing such issue, kindly try to restart your buds:
Just insert the earbuds into the charging case, and then close the lid. Wait 7 seconds or more, and then remove the earbuds from the case.
If the same issue remauns please try to factory reset your buds:
When you perform a reset on your earbuds, all of the settings will return to their defaults. You can only reset your earbuds through the Galaxy Wearable app, and both earbuds must be connected.
First, navigate to and open the Galaxy Wearable app on your Galaxy phone.
Tap Watch settings, tap Reset, and then tap Reset again to confirm.
And check the updats of your buds > Galaxy Wearable: Open the app, and navigate to and tap About Galaxy Wearable or About Samsung Gear app. Then, tap Update.
If the same issue remains, please try to send the logs through Samsung Wearable App:
1- Launch the Galaxy Wearable app on your smartphone within 15 minutes of experiencing your issue
2- Connect your wearable to the Galaxy Wearable app
3- Tap the more icon in the top left of the screen. It will appear as three horizontal lines
4- Tap Contact Us
5- Tap Error reports
6- Fill out the error report with details of what happened
7- Once finished, tap the send icon in the top right of the screen
Let us know if this was helpful