There could be quite a few things causing you to not hear the game sounds. Here are a few ideas to narrow down the issue:

  1. Have you previously heard the game sounds and they've stopped?

  2. If you go to another website, such as YouTube.com, can you hear the sound when playing a video?

  3. Check the game tab's mute button. In Safari, look for a speaker icon on the specific tab's address bar. If you see a muted speaker icon with a line through it, tap it to unmute the tab. Alternatively, check ilovemahj.com in your device settings in case sound has been disabled that way.

  4. Ensure Bluetooth devices are disconnected - in case sound is being rerouted.  

  5. Check the volume on your device is turned up and Do Not Disturb is not switched on.

  6. Are you using a headset? If so, check the volume button on this is turned up.

  7. Have you checked the Game Volumes are up (this option can be found under the gear menu in the game)?

  8. Have you tried restarting your device?