It could be that the story itself has no audio component or there's a glitch in the app you're using. Try restarting the app or your device to see if that helps.
Sometimes, it could be due to a compatibility issue with your device or a poor internet connection. Make sure your internet is stable and that your device meets the requirements for the app playing the stories.
Maybe your device's volume is turned down or there's a problem with the audio settings. Check those first.