"The Messenger of Allah (ﷺ) said: 'Whoever has the habit of praying at night but he sleeps and misses it, that is a charity that Allah (SWT) has given to him, and the reward of his prayer will be recorded for him.'"
Sunan an-Nasa'i Book 20, Hadith 188
← Previous Hadith Aishah, may Allah (SWT) be pleased with her, told him that the Messenger of Allah (ﷺ) said: "There is no man who habitually prays at night, then sleep overwhelms him, but Allah (SWT) will record for him the reward of his prayer, and his sleep is a charity given to him."

Sunan an-Nasa'i Book 20, Hadith 187 Next Hadith → The Messenger of Allah (ﷺ) said: and he mentioned something similar.

Sunan an-Nasa'i Book 20, Hadith 189