Just keep it at the centre for now.
You are just underpowered for your skill level, thats it
Go out in loads of wind, and you can ride easily - and you will soon find out if you want to stand further rear or forward, and can move track accordingly.
And from then you can slowly go out in less and less wind.
I have found that bigger wings tend to have a slightly different trim position, than smaller wings - odd but true.
So little difference that I dont move the tracks though.
Of course wingfoil wings, not hydrofoil wings.... Confusing it is the same word