I was going to say that's not a Uk bird! I guessed it was south African. Not a juvenile sociable weaver is it? Don't think so but I don't know SA birds too well.
Beak looks more finch shaped to me.............so no idea really!
yep it is a Finch, a member of the Canary family - a Seedeater
I was convinced it was going to more exotic Bill!