All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
What you mentioned about the necessity of making up two days of missed prayers each day is the view of the Maaliki School of jurisprudence. Other jurists, such as the jurists of the Hanbali School of jurisprudence, stated that the obligation for a person is to make up prayers in a way that he is not hurt physically or harmed in regard to a livelihood that he needs, regardless of whether he makes up more or less than two days.
Based on this view, you are not negligent if what prevents you from reaching the mentioned limit is work that you need to do, or a harm that you fear for yourself. In any case, you should endeavor to make up the missed prayers according to your ability while seeking the help of Allaah.
You should know that making up for deliberately missed prayers is a matter of difference of opinion among the scholars, and the view of the majority of them is that it is an obligation to make up for them, and this is more prudent and more certain for clearing oneself of their liability.
For more benefit, please refer to fatwa 83724.
Allaah knows best.