Struggling identifying this bird - any help appreciated? Nightingale possibly?

Hey there everyone,

Hope all are keeping well in these continuing times of strangeness.

Managed to get out to a local KWT reserve at the weekend and spotted this bird flitting around on the ground and in low bushes and shrubs and particularly picking off the bark of the tree. I'm struggling to identify it as the colouring doesn't match a warbler as far as I can tell - is this a Nightingale perhaps?

Many thanks for any info

Mark