hi
i tried with different values like,
$vars = array( 'client_id' => 1, 'date_billed' => date('2014-08-16 11:04:03'), 'date_due' => date('2014-08-120 11:04:03'), 'currency' => "USDD", 'lines' => array( array( 'description' => "Line item #1", 'amount' => "5.99" ), array( 'description' => "Line item #2", 'amount' => "3.75", 'qty' => 2 ) ), 'delivery' => array("email") );
$response = $api->post("invoices", "add", $vars);
and
$vars = array( "client_id" => 2, "date_billed" => '20070101', "date_due" => '20070115', "date_closed" => '20070115', "date_autodebit" => '20070101', "status" => 'active',"currency" => 'USD', "note_public" => 'hiiih', "note_private" => 'helooo' );
$response = $api->post("invoices", "add", $vars);
like this