Thank you for reaching out to us. Don't worry, we are here to help.
Following are the guide you have to take in order to change the settings.
Settings > Apps > Tap the 3 dots in the top right > Show System Apps > System UI (green P thumbnail) > Notifications > Tap on 'Battery' > Notification Style (choose Sound or Sound and Pop-Up) > Sound (Select an option from the list)
Hope this content is helpful and your problem gets solved.
If the issue persists, you may contact our Samsung online support channels below.
