Can not install phpmyadmin script

I am on Debian 8, and using Nginx. When I just tried installing phpmyadmin, it exits with the following error:

Failed to install script : The PHP version cannot be set for any directoy except the default for Nginx websites

I only see PHP 5 installed. What can I do to get passed this error?

What repo can we use to install PHP 7?

Has the ability to select PHP version with Nginx been added/fixed yet?

Thanks for any help.