Will Almighty Allah excuse a wife whose divorce was due to her ignorance and negligence, and how can she obtain Allah's forgiveness for her former husband's right when communication with him is impossible, and what should she do about that?

If you have recognized your mistake, repent and seek Allah’s forgiveness, for He is All-Forgiving, All-Merciful, forgiving sins through sincere repentance. If you have wronged your husband, seek his forgiveness, or seek Allah's forgiveness for him if you are unable to seek his forgiveness, for Allah does not burden a soul beyond its capacity. Accustom yourself to fearing Allah in your future husband, and strive to learn the rulings of Islamic law pertaining to the wife so that you may avoid mistakes.