Example with Place Order with OAuth2 is missing in Doc

I am trying to make order and list order with oauth2.
So I already got AccessToken

Also I already have scope


Then I see this in the doc
Wallet API: Buys (Deprecated) | Coinbase Cloud

Buys are deprecated.
Then It guides me to here
Create Order | Coinbase Cloud

Ok. So, i tried to read the Authentication.
Advanced Trade API Authentication Overview | Coinbase Cloud

So it says OAuth can be used with the API
Ok. Now I tried


and it gives me 401 Unauthorized.
All of v2 works fine but all of v3 does not work.

How do I do this?