Last month I played a game of duck race with a friend, and this happened in the blackjack challenge.
Person has a 3 of hearts and an ace of hearts for a total of 14.
Person draws a 10 of hearts for a total of 14.
Person draws a 6 of spades for a total of 20.
I know an ace can either be 1 or 11. So either in this example, the ace was 1 and reported as 11, or it was 11 and the 10 is bugged.

Hello,
sorry but I don't understand where the bug is.
first, person had ase and 3 which adds up to 14.
here the ase is counted as 11.
next the person drew a 10, now if the ase continues to be counted as 11, the person will end up busting.
hense, the ase is counted as 1. which means 10 + 3 + 1 = 14.
then, he drew a six to add up to 20.

so, if the total is going to be less than or equal to 21, then ase will be counted as 11, if it is going to be higher than 21 it will be counted as 1.

Can an ace change like that based on the circumstances? I think it can, which is why I didn't call this a bug with certainty. But if it can't, then this has to be a bug.

Hello,
basically, the explanation provided by @sky360 is correct and there are no bugs here.

If you try the Black jack game itself, it works exactly the same. An ace always gets the value that is currently not causing the player to go over the limit of 21.