In such case, try changing the "{{% livechat_label prosody_peertube_uri_label %}}" settings, by setting `http://127.0.0.1:9000` (assuming 9000 is the port on which Peertube listen, ask your instanceadministrators if you don't know).
If everything is fine in the diagnostic tools, but chat windows remains empty: it can be a Websocket issue.Since Peertube version 5.0.0, there are some additional configuration to do on the server side.Check with the instanceadministrators that they did not forgot to apply changes listed in the [Peertube v5.0.0 release notes](https://github.com/Chocobozzz/PeerTube/blob/master/CHANGELOG.md#v500).
If you can't fix this immediatly, you can disable Websocket by unchecking "{{% livechat_label disable_websocket_label %}}" in the plugin setting page.In such case, you should also check "{{% livechat_label federation_dont_publish_remotely_label %}}", as chat federation won't work without Websocket.
[OBS](https://obsproject.com) is a popular Free And Open Source streaming software, with advanced capacities for your live streams.In the current page, you will find some advices to handle your live chats using OBS.
![Screenshot of a Peertube live, replay, with the chat included at the bottom of the videostream.](/peertube-plugin-livechat/images/embed_chat_in_livestream.png?classes=shadow,border&height=200px "Embeding the chat in a livestream")