Adspace Plugin Api Key Link not working

I have downloaded Adspace plugin from this link https://wordpress.org/support/plugin/adspace-platform.

I am not able to get the API Key to activate. The Link given to get the API Key is: https://www.ad-manager.org/ad-manager.html#myadspaces whcih is not working. Please help me to get the API key

https://wordpress.org/plugins/adspace-platform/