We try to ensure videos play on every device. But in some rare instances your device or browser may need to be updated or some settings need to change.
The easier option is always to try a different browser on your phone, ideally the latest version of Chrome and ensure that you have good internet connection.
If the error message says “Video Not Available”, refer to this article on a setting in your browser that may prevent videos from playing.
Last but not least, try a different device and that should take care of this.