Is a Muslim girl permitted to pray while not wearing the hijab, knowing that she has circumstances preventing her from wearing it?

The prayer of an adult woman is not valid unless she covers her awrah (private parts), based on the saying of the Prophet, peace and blessings be upon him: "Allah does not accept the prayer of a menstruating woman except with a head covering (khimar)." The term "menstruating woman" here refers to one who has reached the age of menstruation.

As for the prayer of a woman who does not adhere to hijab outside of prayer, her prayer is valid, and she must perform the prayer at its prescribed time with all its conditions and pillars. Neglecting prayer or abandoning it is not permissible, no matter how numerous the sins. Rather, it is obligatory to repent to Allah and hasten to do so.