Set group while registration

Hi

I’d like to add all new users into a group. The registration goes over woocommerce form.

add_action('woocommerce_created_customer', 'add_to_UAM');

function add_to_UAM($user_id) {
	$wp_uid=$user_id; //WordPress user ID
  	$userGroupId=6; // Group ID to be updated

  	global $userAccessManager;

  	$uamAccessHandler = $userAccessManager->getAccessHandler();
  	$uamUserGroup = $uamAccessHandler->getUserGroups($userGroupId);

  	$uamUserGroup->addObject('user', $wp_uid);
 	$uamUserGroup->save();
}

I’ve added this code into the functions.php. That’s the error:

Fatal error: Call to a member function getAccessHandler() on a non-object (at this line: $uamAccessHandler = $userAccessManager->getAccessHandler();)

Is an import missing or something? Maybe someone can help my out that would be great.

btw is there an api? can’t find it XD

https://ww.wp.xz.cn/plugins/user-access-manager/