How can I protect myself from my manager's treachery at work and rely on God to facilitate my affairs?

Officials must rule with justice, for they are accountable to Allah for their subjects. Whoever does not rule justly will come on the Day of Resurrection shackled. The best way to repel their injustice is through piety towards Allah, patience, and seeking forgiveness. You may supplicate against them if you are certain of their injustice. Among the well-known supplications is: "O Allah, we place You against their throats and we seek refuge in You from their evils."