A Hospital Management System (HMS) is a software solution designed to streamline and optimize the administrative and clinical tasks within a healthcare facility. It serves as a centralized platform for managing various aspects of hospital operations, including Patients, Appointments, Doctors, Specialization and Doc_Specialization_Mapping.

Task:

Write an SQL query to display the FirstName and LastName of all patients who have taken at least one doctor appointment and whose ContactNumber and Email are not provided. Consider a value as not provided when it is NULL, an empty string, or contains only blank spaces. Sort the result in ascending order of FirstName.