I have exactly the same problem with my Galaxy Book 2 Pro 360 using the original cable and adapter. I think it happened after a Windows update or Samsung firmware update and is not hardware related.
@jamie_w Did you solve it?
It started charging again like normal after I unplugged it and did a full shutdown (shift + shutdown). I still don’t know what caused it but I’ve had no problems since then.
That's definitely not what I'd expect, @congavri. If you're based in the UK, I'd recommend going through the steps outlined on the self-service repair portal here:
Just choose the Computing option > Galaxy Book. You will then be taken on a repair journey, as it were. If the steps do not help you resolve this, you will be able to book a repair. Should that need to be arranged, our Product Specialists will call you to advise you about the next steps.