Is the monthly salary that an employee receives without working after being dismissed from his job and those less qualified than him being promoted lawful or unlawful?

You have done well in exerting effort in your work and bearing witness to the truth. There is no blame upon you for the financial dues you receive, because your ruling with your employer is like the ruling of a private employee who is entitled to the full wage by dedicating himself for the period, whether he is assigned work or not.