I have it off already. Been paradoxically thinking of re-enabling it to see if it makes a difference. But that would cause other issues (with face recognition while wearing sunglasses etc)
Just to be clear, there are two “attention” settings. It sounds like you might be confusing the two…
Require Attention for Face ID - Turning this off makes it so you don’t have to be looking directly at the screen for attention. Just looking ahead, eyes off to the side, or eyes closed will give the phone attention. (Turn this one off if your particular pair of sunglasses is giving you issues with Face ID.)
Attention Aware Features - Turn this off if you want your phone to autolock even if it still has attention.
So... If you have the first one off and the second one on, your phone is not going to autolock because it’ll think it has attention even if you aren’t looking directly at it. You’ll either want the first one on (and the second one on or off), so that it autolocks when you aren’t looking directly at the phone. Or turn the second one off if the first one is off, so that it’ll autolock even if it thinks it still has attention.