This means that the wrong mask was given or element at the specified mask is not available to make a click or it's a consequence of incorrect software operation - if you sure in this, please contact technical support service and provide the necessary details (login, id folder and task id).
Such a situation is typical for the elements that are dependent on various parameters, including the factors associated with the IP-address of the visitor. However, this may be due to incorrect operation of the software - if you sure in this, please contact technical support service and provide the necessary details (login, id folder and task id).
This means that sometimes in some reasons elements on the given mask were not found, or this means the absence of elements. This situation is typical for elements displaying of which depends on various parameters associated with the IP address of the visitor.