Surah Al-Anam · Ayah 31

Those will have lost who deny the meeting with Allāh, until when the Hour [of resurrection] comes upon them unexpectedly, they will say, "Oh, [how great is] our regret over what we neglected concerning it [i.e., the Hour]," while they bear their burdens [i.e., sins] on their backs. Unquestionably, evil is that which they bear.

Translation: Saheeh International