Assalamu alaikum wa rahmatullahi wa baraktuh,
Narrated Awn Ibn Abu Juhaifa
"My father said, I saw Bilal turning his face from side to side while pronouncing the Adhan for the prayer."
[Sahih al-Bukhari]Sahih al-Bukhari
"I saw the movement of his mouth from this side to that side upon saying "Hayya 'alas-salah" and "Hayya 'alal-falah."
[Musnad Ahmad]
"I saw Bilal calling the Adhan, and turning, and his (face) was following here and there, and his (index) fingers were in his ears"
[Jami at-Tirmidhi]Jami at-Tirmidhi
It is Sunnah to turn slightly to the right upon declaring ‘Hayya alas-Salaah’ and to the left upon declaring ‘Hayya alal-Falaah’ during the adhan and the iqamah; but if for any reason one forgets or does not do so, the ‘Adhan’ will still be valid.
And Allah alone knows best
Wa assalam
