Create site error "Error: Please allow function : json"

Problem

When you create a website, it error.

Error: Please allow function : json

Reason

RVsitebuilder requires PHP function "json" to enable but it's disabled for your domain name.

Solution

Just simply enable PHP function for alt-php (CloudLinux)

For your domain name

If MultiPHP INI Editor is available on your cPanel account package. 

1. Login to your cPanel.
2. Select MultiPHP INI Editor under a Software category.
3. Switch to Editor Mode.
4. Select a location.
5. Remove "json" on "disable_functions" and Save.

For the entire server

1  Log in to WHM
2. Go to Home->Software->MultiPHP INI Editor.
3. Choose the Editor Mode tab.
4. From the drop-down list choose the PHP version.
5 .In the configuration window that will be opened, search for “disable_functions”.
6. Remove "json" on "disable_functions" and Save.