1. Sometimes the reason why we can't play twitter videos is that the network connection is bad. In this case, you can connect to a stable network and restart the Twitter app to load the video again.
2. Clear all caches and cookies from your computer/device browser from your browser's Settings menu.
3. If the Twitter app on your device has not been updated for a while, try updating your Twitter app to the latest version and play the videos again.
4. Sometimes, old browsers are the cause that we can't play videos on Twitter, so you can fix them by updating your browser to a new version.
5. Some plugins, security software and firewall programs may lead to the videos won't play on Twitter issue. This could be fixed by disabling these programs on your computer.
6. If you upload a video to Twitter, please make sure it conforms to Twitter Video Specs. Otherwise, the video won't play either or you will get an "Your Media File Could Not Be Processed" error.
If you want to upload video to Twitter, keep the specs for Twitter video upload in mind:
Video format: MP4 for web; MP4 or MOV for mobile app.
Codec Format: H.264/AAC-LC
You can upload a maximum of 512MB video, and the video length is no longer than 140 seconds.