Hello I pressed 'Split' on two aces. The second hand was blackjack and it instantly stood the first and second hand as soon as i pressed split making one of them lose instantly. Is that supposed to happen because i don't think it should?

Same think just happened to me I lost on a 13 that got split and won on a 19. When you split you should still be able to hit.. the system is flawed..

If you split aces, you can't hit any more. It's a single card.
You'll find a lot of card houses with similar rules in terms of splitting Aces.

If you hit a blackjack with the aces, it still pays out 1.5 to 1. Giving the user the ability to still hit with the safety net of having the Ace act as a 1 is too much of an advantage for the house to give users that ability.

Also, if you split any other cards, you cannot Split again or Double Down. This isn't too common in card houses, however it's how MafiaReturns blackjack is set.