If I miss a prayer, am I accountable for a sin?

Delaying prayer beyond its prescribed time without a valid excuse is a grave sin, as Allah the Almighty says: "So establish prayer. Indeed, prayer has been decreed upon the believers a time-restricted ordinance" (Quran 4:103). And He says: "Then, there succeeded them a later generation who neglected prayers and pursued desires; so they are going to meet ghayy" (Quran 19:59), meaning they delayed them beyond their times. However, if the delay is due to an excuse, sleep, or forgetfulness, there is no sin, as the Prophet (peace be upon him) said: "Indeed, Allah has pardoned for my Ummah three things: error, forgetfulness, and what they are forced to do."