Is there repentance for one who unintentionally cursed Allah, the Mighty and Exalted, and then regretted it?

There is nothing that stands between a servant and repentance. Allah the Almighty said: "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful.'" And Allah the Almighty promised those who commit the greatest sins, such as disbelief, that He would transform their evil deeds into good ones if they repented, believed, and did righteous deeds, as in His saying: "Except for those who repent, believe and do righteous deeds. For them Allah will change their evil deeds into good ones. And Allah is Forgiving and Merciful." Therefore, one must hasten to repent.