@Sekhonfamily 

Hi, 
Can you hear the sound on the camera's Live View page? If so, on the camera's Device Settings > Storage & Recording page, please enable the Record Sound option, and then check if the video recordings will have sound.

If the problem remains, please confirm the following information.
  1. The model number and MAC address of your camera. You can send me(@Solla-topee) the MAC address via a private message.
  2. Are the video recordings stored on an SD card inserted into the camera or our cloud server?
  
Best Regards