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, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
There is no doubt that a person may be tested by themselves, their family or money as atonement for sins and a means to elevate his rank if he is patient. Undoubtedly, what the questioner mentions is a test that may be due to envy or the evil eye.
If this is the case, you must recite the holy Quran and make supplications and invocations to Allaah The Almighty so that He will relieve this affliction.
However, this test may also be the result of ordinary factors like a changing market, large number of competitors and so forth. Thus, you have to exert efforts to change this if possible. In addition, you have to seek refuge in Allaah The Almighty and supplicate Him to make things better. Moreover, you should not yield to these whispers because it may lead to dire consequences.
Finally, having an internet café requires the observance of certain restrictions so as not to violate the Sharee‘ah (Islamic law) so that the profits are lawful.
Allaah Knows best.