Any error messages should be in the log files under logs/ within the root directory of the bot.
If this file doesn't exist the permissions of the root directory are probably wrong.
First, make sure that you have set up the server permissions correctly as mentioned in the Permissions section. In addition to this, you might have to enable the "Show ServerQuery Clients" setting in your TeamSpeak client under Bookmarks->Manage Bookmarks and reconnect to the server. You might have to enable advanced settings for this.
If you still cannot see the bot after reconnecting, check if the bot is really still connected by checking the logs of both the bot and the server. If you cannot find the problem, feel free to open a new issue.
The bot can only handle commands via direct message. If you are sending a direct message and the bot still does not react, try setting the permissions as mentioned in the Permissions section.
Your query_timeout parameter in the ts3server.ini file is probably very low (<10 seconds).
Please set it to a higher value or 0 (this disables the query timeout). If this does not fix
it, feel free to open an issue, there might still be some unresolved problems here.
You need to whitelist the IP the bot is connecting from in the Teamspeak configuration file. To do this
change the file query-ip-whitelist.txt in the server directory and add a new line with the IP of your bot.
The bot writes quite some logs in the root directory. Check those for errors and open an issue if the issue remains.
Update the bot! Server version 3.4.0 changed the way the query timeout was handled.
Versions of the bot older then 17. September 2018 will not work correctly.