What is Islam's stance on mentally ill individuals when they commit sins, and what do they do to expiate them? And what is fitna, and is it a trial? And what is zina, and is a phone relationship between a man and a woman considered zina?

A mentally ill person is not held accountable if their mind or will is taken away, but whoever is aware of their actions is responsible for them. Repentance is by abandoning the sin, regretting it, and resolving not to return to it, and restoring rights if the sin relates to a human right, along with increasing good deeds. "Fitna" linguistically means testing and trial, and in Islamic law, it may mean corruption, fighting, or harm. The fornication (zina) that necessitates the legal punishment (hadd) is the intentional sexual intercourse by a legally responsible Muslim with the private parts of a human being over whom he has no ownership or شبهة (semblance of right), and it is a major sin. The relationship between a man and a strange woman over the phone is not the zina that necessitates the hadd, but it is a path to indecency, and the Prophet, peace and blessings be upon him, called it zina in the hadith: "The son of Adam's share of zina has been decreed for him..." the Hadith.