【Possible causes】
1. You have muted the audio.
Please select the speaker symbol to unmute the sound.
Muted state
Sound will be heard.
2. You are viewing an image post.
If you are viewing an image-only post, no sound will be heard.
Please check again to make sure that you are not viewing an image post.
3. There is no audio in the video itself.
If you still do not hear any sound after following the steps in step 1, you may have turned off the sound in your video.
4. The sound on the device itself is turned off.
Please check if the sound on the device is muted or the volume is set to 0.