If one of them is a ten, it is not a blackjack, it is just 21 points. Also, please note that it is a standard blackjack rule that split aces get one card each. However, that is a basic strategy exception.
As a rule of thumb, the player should stand in that situation. I have also had many comments about the advice on a player 16, composed of 3 or more cards, against a 10. This usually can be explained by the user not using the correct basic strategy for the rules selected. I get a lot of incorrect reports that the advice given is incorrect. A screenshot would be appreciated if you claim the game is misplaying a hand. The deck(s) is(are) shuffled after every hand. The advice is based on my own analysis and basic strategy tables for one, two, and four+ decks. If you do, the change will not take effect until the next hand. If doubling or splitting is mathematically the correct play, but you don't have enough chips, the game will give the best advice for what you can afford to do. I recommend that before you play for real money both online in person that you practice on the game until you very rarely are warned you a making an inferior play. If you make an inferior play, the game will warn you first. This is our first blackjack game and trainer and I'm proud to finally add our version 2 with enhanced graphics and the ability to learn how to count cards to my website.