Is it permissible to speak with a non-mahram woman over the phone about matters of religion, health, or family?

There is no objection to a man addressing a woman or a woman addressing a man to achieve a legitimate objective, such as teaching religious or worldly sciences that benefit society. The proof for this is the hadith of Abu Sa'id Al-Khudri, in which the women asked the Prophet, peace and blessings be upon him, to dedicate a day for them, so he admonished and instructed them.

When addressing a man, a woman must not speak in a soft, alluring tone, and she must cover her entire body and lower her gaze. Likewise, a man must lower his gaze and limit his interaction to what is necessary.