Hello xoxoyazyxoxo, let's get to the bottom of this! Have you check the notification sound settings on the device? To do this, go to Settings, Select Sound in the "My Device" tab, click Volume and it will show the notification volume. Make sure that the volume is turned up and then test. Are you experiencing any other issues with sound on the device such as ringtone when calling? Keep us posted!
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Thanks for the details xoxoyazyxoxo. To be able to check your notification sounds for facebook, you would need to open the app, then go to the settings > then notification settings should be available from there to choose. If you have additional issues with Facebook, you would need to contact there support team as we can not support third party applications. Thanks for your patience and for further support click here http://bit.ly/yN1P80
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