DA API domeinveranderen werkt niet

<table>
						";
											if(!empty($_POST['old_domain']) && !empty($_POST['new_domain']))
											{
												$old_domain = $_POST['old_domain'];
												$new_domain = $_POST['new_domain'];
												
												$sock->query('/CMD_CHANGE_DOMAIN',
												array(
												'old_domain' => $old_domain,
												'new_domain' => $new_domain,																					
												));


											}
											echo'
											

											<tr>
												<form method="POST">
												<td width="290" colspan="2">
													<input type="text" name="old_domain" class="textarea" value="Oud domeinnaam"/>
													<input type="text" name="new_domain" class="textarea" value="Nieuw domeinnaam"/>
												</td>
												<td width="10"><input type="submit" name="factuur" value="Toevoegen"></td>
												</form>
											</tr>
									</table>