when i try to activate the demo content it show this:

You don't have any purchase of Kalium from Ahsath Envato account!

and on this page it says:

Envato API is having some issues and this causes theme activation not to work properly. Please bear with us until this is fixed.

{"wp":{"use":false,"adminUrl":"","username":"","password":""},"ftp":{"use":false,"url":"","port":"","user":"","password":"","path":""}}