Does the divorce issued by the husband on previous occasions take effect, given his belief that his wife would return to him simply by cohabiting, and after he learned that repeating the pronouncement leads to an irrevocable separation?

If the husband has divorced his wife with three pronouncements of divorce while fully aware of what he was saying, then she has become irrevocably separated from him (baynunah kubra). She is not lawful for him again unless she marries another man, according to the words of Allah the Almighty: (And if he has divorced her [for the third time], then she is not lawful to him afterward until she marries another husband). It is advised to go to the Sharia court and explain in detail what has happened.