He is being asked to erase the faults shown by the computer so that the customers will not see them
Question

                After several years of seeking, I finally found a job in a company in the private sector, but my problem is that along with other office work, I am being asked to prepare and print reports so that they can be included with the final technical file. These reports are produced automatically by the testing devices used, after they are connected to the work being done on site. What is worrying me is that I am being asked to tamper with these reports on the computer and erase all the faults that are shown by the computer in the form of a graph. What is required if any faults show up is for the workers to go back to the customer and correct it, but if the customer sees the report coming from the computer showing no faults, he pays the bill, because this report has a great deal of credibility and it is difficult to falsify it except by using the highly-developed program installed on the computer. I hope that you can tell me the solution and help me to put my mind at rest.
Praise be to Allah.Tampering with the reports 
    as you have described is cheating and betrayal that is not permissible, and 
    it leads to the consumption of people’s wealth unlawfully. 
Everyone who takes part in 
    this cheating is sinning. 
The buyer should be told of 
    whatever faults exist in the work that has been done, then if he accepts the 
    work regardless, all well and good, otherwise the workers should fix it as 
    you said. 
Muslim (101) narrated from 
    Abu Hurayrah (may Allaah be pleased with him) that the Messenger of Allaah 
     (peace and blessings of Allaah be upon him) said: “He who deceives us 
    is not one of us.” 
Al-Bukhaari (2079) and 
    Muslim (1532) narrated that Hakeem ibn Hizaam (may Allaah be pleased with 
    him) said: The Messenger of Allaah  (peace and blessings of Allaah be 
    upon him) said: “The two parties to a transaction have the option (of 
    cancelling it) until they part. If they are honest and disclose any defects, 
    their transaction will be blessed, but if they lie and conceal defects the 
    blessing will be erased.” 
It should be noted that 
    provision is something that has been decreed by Allaah before He created the 
    heavens and the earth, so do not be tempted to seek provision by disobeying 
    Allaah if it seems to be slow in coming. 
The Prophet  (peace and 
    blessings of Allaah be upon him) said: “The Holy Spirit (Jibreel) has 
    inspired to me that no soul will die until it has completed its appointed 
    term and received its provision in full, so fear Allaah and do not be 
    desperate in seeking provision, and no one of you should be temped to seek 
    provision by means of committing sin if it is slow in coming to him, for 
    that which is with Allaah can only be attained by obeying Him.” Narrated by 
    Abu Na’eem in al-Hilyah from the hadeeth of Abu Umaamah; classed as 
    saheeh by al-Albaani in Saheeh al-Jaami’, no. 2085.  
What you must do is advise 
    those who are in charge of the company, and explain to them that cheating is 
    haraam and what its consequences are in this world, as it takes away the 
    blessing, and in the Hereafter it brings punishment for wrongdoing and 
    consuming people’s wealth unlawfully. If they respond, then praise be to 
    Allaah, but if they do not respond, then you should ask to be moved to an 
    area where no sin is involved. Otherwise, look for work elsewhere. 
“And whosoever fears 
    Allaah and keeps his duty to Him, He will make a way for him to get out 
    (from every difficulty).
3. And He will provide 
    him from (sources) he never could imagine. And whosoever puts his trust in 
    Allaah, then He will suffice him. Verily, Allaah will accomplish his 
    purpose. Indeed Allaah has set a measure for all things”
[al-Talaaq 65:2-3]
We ask Allaah to grant you 
    abundant provision and to bless your wealth for you, and to make you 
    independent of means by that which is halaal so that you have no need of 
    that which is haraam. 
And Allaah knows best.