Answer
Rasulullah (Sallallaahu Alayhi Wasallam) kept a full beard which covered the above portion of his chest. There are three narrations regarding the size of his hair: a) Till the ears, b) below the ears, c) till the neck (shoulders).
All three narrations are correct as hair continuously grows. (Shamaail Tirmidhi).
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai