I think it can depend on your TV and what software it has. I've subscribed to watchnrl.com and it won't cast to my LG Smart TV but will cast to my son's LG Smart TV that just happens to be a year newer.

Cured it by plugging an HDMI lead into my laptop and then into a spare HDMI socket on the TV. Watched 7 NRL games this weekend (including the Sky ones). Loving it. And the Super League starts next week!

I’m almost 70 and understand . Do all that stuff when caravanning.

Enough said

So I've just been telling my friend that they can pay for the game on Our League App as a one off but now I've looked it seems you can only do that for championship.
Am I wrong.
Is the only way to watch to buy a season ticket?
Bit of a revenue miss if that is the case.

Yes, it’s just the championship you can purchase a game. I think Sky wanted to help SL clubs increase their revenue by increasing the season ticket sales, allowing fans access just to their team games. To be fair to Sky, allowing fans to access both home and away games, i this quite generous.