What is the ruling on a taxi driver giving a ride to a woman alone if the law prohibits refusing that, and what is the ruling on the fare, and what do you advise?

The Prophet, peace and blessings be upon him, forbade a man from being alone with a non-mahram woman, due to his saying, peace and blessings be upon him: "No man should be alone with a woman unless there is a mahram with her," and his saying: "Indeed, no man is alone with a woman but Satan is the third of them." This privacy (khalwa) often occurs with taxi drivers in side streets or isolated areas. Even if complete privacy is not achieved in crowded streets, their being alone together in the car can lead to unlawful gazing and falling into what is forbidden, and unlawful means take the ruling of their unlawful ends. The fatwas of the Permanent Committee have clarified that forbidden privacy includes any seclusion that leads to secret talks and conversations, even if it is in plain sight of people without them hearing their conversation, because it is a prelude to adultery.

You must avoid this forbidden act as much as you can. If that is difficult for you, then make your route within the city as much as possible to avoid complications. If your livelihood is affected by refusing to give rides to women, then there is no blame upon you for giving them rides to ward off harm from yourself, provided that the woman sits in the back seat, and you avoid looking at her or speaking with her unless necessary. If you can find another job that has no prohibitions, it is better for you.