You can only edit Live Houses that you have added. When logged in, open the page of the Live House you want to edit and you will see an icon on the top, next to the title. Click this and you can edit it. 

To access a list of all the Live Houses you have added, select MY LIVE HOUSES from the PROFILE or LIVEHOUSES menu dropdown on the top of the page.

You cannot edit an item that you didn't add. Message admin instead.

You can also delete your live houses from the MY LIVE HOUSES page.