Registration api does not work

I have installed your api in my local server. After install i tried to register a user using link http://localhost/wordpress/wp-json/wp/v2/users/register and method was post. Also i set parameter like below..

{
“username”:”abcdef”,
“email”:”[email protected]”,
“password”:”12345678″
}

It display 400 error with message “Username” field is required.

Please let me know how to solve the issue.

Thank you