Narrated Abdullah ibn Umar:
Bilal made a call to prayer before the break of dawn; the Prophet (ﷺ), therefore, commanded him to return and make a call: Lo! the servant of Allah (i.e. I) had slept (hence this mistake).
T…
Nafi' reported : A mu'adhdhin of ‘Umar, named Masruh, called the Adhan for the morning prayer before the break of dawn; ‘Umar commanded him (to repeat). The narrator reported the tradition in a similar way.
Abu Dawud sa…
Narrated Bilal:
The Messenger of Allah (ﷺ) said to Bilal: Do not call adhan until the dawn appears clearly to you in this way, stretching his hand in latitude.
Abu Dawud said: Shaddad did not see Bilal.