He was absent from work with the permission of his immediate boss, but without the management’s knowledge
Question

                I found a job as a customer service representative in Egypt. We had to sign a contract, the terms of which are as follows:

A two month training period during which the salary is 3500 Egyptian pounds per month;

after completion of the training period, the salary will rise to 4000 Egyptian pounds per month.

We are not allowed any days off during the first six months. During the training period I was forced to take a week off for my wedding. The trainer told me that this wedding break would be a secret between me and him, without the management’s knowledge, because I was not entitled to any break during the training period. I got 3500 pounds at the end of the month. Is the money that I got for the week off haraam? If it is haraam, what should I do?
Praise be to Allah.
    The basic principle is that the employee is required to 
    fulfil the conditions stipulated in the contract, so long as those 
    conditions are not contrary to Islamic teachings. Allah, may He be exalted, 
    says (interpretation of the meaning): “O you who believe! Fulfill (your) 
    obligations” [al-Maa’idah 5:1]. And the Prophet (blessings and peace of 
    Allah be upon him) said: “The Muslims are bound by their conditions, except 
    a condition that treats something halaal as haraam, or treats something 
    haraam as halaal.” Narrated by at-Tirmidhi, 1352; classed as saheeh by 
    Shaykh al-Albaani in Saheeh Sunan at-Tirmidhi. 

    If the matter is as you say, that your immediate boss is the 
    one who gave you time off and the company did not tell him to do that, and 
    the system does not allow that, then it is not permissible for you to take 
    this break just because your immediate boss agreed, because that is breaking 
    the terms of your work contract. So you have to return to the company the 
    money that you took for the time you had a break, even if you have to resort 
    to some kind of trick, as appropriate; you do not have to tell them what 
    really happened. 

    And Allah knows best.