Hello User24985,
Welcome to the Community page,
Currently, Natwest International bank accounts in the Channel Islands are not on Open banking as of yet. So you will not be able to connect them to a live feed as there is not one available at present on the new open banking. If you are needing the transactions in the system for this account, it would be a case of having to CSV them in until an available feed is on open banking. This link will also tell you when it becomes available on open banking.