wp-rest-api-disable-relevanssi.php

function disable_relevanssi_prevent_default_request($param1, $param2) {

	global $wp;

	if ( strpos( $wp->request, 'wp-json' ) === 0 ) {
		remove_filter( 'posts_request', 'relevanssi_prevent_default_request' );
	}

	return $param1;

}

add_filter('posts_request', 'disable_relevanssi_prevent_default_request', 11, 2 );