Been having some trouble with fuel settings for long hauls. Not sure why. Maybe someone can help me?
What kind of trouble are you talking about?
Just bring 2 hour more fuel than your actual actual flight time, that should be good enough for you to reach the destination or divert to a nearby airport. Ex:VHHH-KLAX which is 12 hours of flying and I will bring around 14hours of fuel, that could ensure me to have enough fuel to reach KLAX
This link is also helpful for fuel calculation and see what flight level is the most suitable for your fuel burn. You can give it a try!
also something to take into account, you will weigh less throughout your flight and thus burn less fuel, so even if you ETA starts screaming at you saying you won’t make it, you will
Your best bet is using something like Simbrief or FPLtoIF