Is it permissible to file a lawsuit against a company based on the terms of labor law if the employment contract contained unfair conditions to which the worker agreed, and the company did not violate the text of the contract?

If the worker agrees to waive some of his rights in the contract, then he is not entitled to claim anything other than what was agreed upon by both parties, due to the Almighty's saying: "O you who have believed, fulfill [all] contracts," and the Prophet's (peace be upon him) saying: "Muslims are bound by their conditions." Custom and common practice are considered in the absence of explicit statements to the contrary, but if a condition exists, it must be acted upon.