You are an Acquia Cloud Enterprise customer, trying to enable Live Dev for your development/test environment and it is failing.
Check the the task log on Acquia Cloud for the particular task id associated with enabling Live Dev. If in the task log you see error like -
No space left on device
While enabling Live Dev, the currently deployed code is copied over to a location -
~/[env]/livedev, if this location does not have enough disk space, you can get the above error. You can check the available disk space following - Accessing disk space usage.
In case of any concerns or issues please contact Acquia Support via support ticket.