He does look unkempt, rumpled, like he just got up from a nap. I wonder if he is having post -stroke issues? Strokes are tough to recover from (i mean, it’s possible, but it’s hard) and he’s had a lot of stress lately, which really can’t help.
His colleagues probably dressed up to meet him - but royals have to be careful, because there's the risk of being the only one in the room with a tie.
Also, this may be the tail end of his working day.
I think he looks OK.