In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
So long as public transport laws ban using private cars for transporting paying passengers, then they must be adhered to.
Answering your question, the General Iftaa’ Department in Jordan, states the following:
In principle, different works and professions are permissible so long as they don’t violate the Shari`ah since Allah, the Almighty, said, “And when the Prayer is finished, then may you disperse through the land, and seek of the Bounty of God.” (Al-Jumu`ah 62:10)
However, so long as public transport laws ban using private cars for transporting paying passengers, then they must be adhered to.
In this regard, Muslim scholars have made clear that the ruler may restrict the permissible if that lies in the best interest of the people, wards off harm and doesn’t violate the Shari`ah texts (Quran & Hadith).
In conclusion, public transport laws must be abided by when operating private cars for transporting paying passengers to ensure that public interest is observed.
Almighty Allah knows best.