Firstly, make sure you are using the correct prefix. You can find it by @mentioning Gami in a text channel. If it still doesn't respond, make sure it has adequate permissions.
To find a list of commands, type
-help in a server with Gami.
To change the prefix, simply type
-prefix <new_prefix> in a server with Gami. If you don't know the current prefix, try mentioning Gami.
To enable auto-role, type
-autorole <role>. Make sure that Gami has a role above your auto-role, or it will not be able to function correctly. To disable auto-role, just type