You can amend or change the name and end date of your organisation site using the Site Update tool (Please note that you can not change the name or end date of a module site, as the information for module sites comes from SITs).
Step 1. On your organisation site, from the right-hand menu under [Details and Actions], select [My Tools]
Step 2. From the next menu, select [Site Update].
Step 3. Once the tool integration has loaded, you can change the name of your organisation site and extend the end date. Click the [Update Site] button to apply the changed when you are finished.