Small bird (smaller than a robin, for example, with distinct white brow and collar, black eyes and bill, dark legs, russety breast, brown back heavily streaked black.
This is a good description of a male Stonechat.
As Cris says,
I wonder if this RSPB on here, website a-z may clarify for you.
https://www.rspb.org.uk/birds-and-wildlife/stonechat
Duplicate post from yesterday, which was answered by a different member, also as a stonechat
No, did not have the black head and had a vey definite white brow.
Female stonechat then.