Every time I receive a call from a number like this, I block it. But they keep doing it, they ask for James. This time when they said "Can I speak to James" I said "yes" and they immediately hung up. Who are they adn what are they doing?

Rang after 7pm. The usual long pause before anyone speaks. Took that second to hang up.

yeah same thing for me mate

Calls from this number, but immediate hang-up.
Don't bother to call back.

Yes scam when called back says disconnected