Should a person search for the reasons behind the difficulty in their sustenance, or is it enough to rely on Allah and supplicate?

One is not obligated to investigate whether they are afflicted by the evil eye or envy, or if there is a cause preventing sustenance, for no scholar has ever stated that this is obligatory. Rather, if a servant becomes aware of a cause, they should strive to remove it and are required to exert lawful efforts in seeking sustenance. If one feels afflicted, they are commanded to seek healing and protection.