Click on the "Edit body details" button. If you don't see it, that means you are not a board member:
This page will appear. The fields that you cannot change (e.g. you cannot change the type of the body if you are a board member, only CD can do this) would be disabled (in my case, body name, code and type are disabled):
Change it to whatever you want and press "Save". You should see the "Body is saved" notification and the body page should display the updated info.