Still trying to learn this game

Situation: 2 outs. 1st and 2nd. Batter gets a SINGLE**. What kept the runner on 2nd from scoring? Thanks.

HAL being HAL ?

Runner on 2nd tripped on his shoe laces?

Covid Precautions?

I'm new to the online game but when this happens on the PC I believe it's due to the "more baserunning decisions" option, which is apparently active online as well: https://stratomatic365.fandom.com/wiki/Maximum_Rules

Thank you.

That is an example of a max rules option that probably should not be selected in the online game. More Baserunning Decisions is meant for the face-to-face (or face to computer) player--not for HAL.

Another black box-ism that in this case makes SINGLE** results uncertain.
It probably doesn't come up much, but it shouldn't come up at all.