What should I do, as my mother's harsh prayers against me have been answered, making my life miserable, and is there any supplication that can prevent her prayers from being answered?

It is obligatory to hasten to repent to Allah for disobeying one's mother, as it is one of the greatest major sins and a cause of abandonment. Repentance involves ceasing the sin, regretting it, and resolving not to return to it. Among the signs of sincere repentance are apologizing to one's mother, striving to appease her, treating her with righteousness, and showing kindness to her. If your repentance is sincere and you steadfastly obey Allah and treat your mother with righteousness, then rejoice in the acceptance of your repentance, success, and prosperity, for "the one who repents from sin is like one who has no sin."