If you want more replies it's helpful to give more information such as what is the piece for, what areas do you think need work, what style are you trying to achieve etc. That aside a couple of points:
His skintone is very yellow. Granted, he may have an olive complexion but this is more green yellow than peach yellow.
Head too far forwards. If you tilt your head to match his angle, your chin will almost touch your neck and is much closer to your chest.
Character and background styles are different which sets them at odds. A unifying direction and color temperature for the light would help overall. Hope this helps, Cheers
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His neck also seems really long, to go with the "head too far forward" comment made previously (which I agree with).
Everything in your painting has a shadow, a mid tone, and a highlight, which is generally a good idea (and a lot of times you might want reflected light). The problem is your highlights are all so small and very far forward in value than the adjacent values. This gives the feeling that everything is made of the same material as his skin, boots, clothes, etc. He looks like a plastic statue rather than a standing person.
Observe- a lot of fabrics don't have what you would call "high lights."