Normals auto-smooth question

Hello someone to tell me as , why are there numbers of situations where autosmooth appeared grey , thus not editable?
As:
2022-2_16-

i’ve never got this.
Thanks in advance,

Because you need to check the box next to it to turn Auto Smooth on.

it defines the angle formed between 2 faces from which there will be autosmooth or not,
you must check the box to activate the autosmooth and be able to adjust it.

Capture d’écran 2022-05-16 103340

And if it’s checked and still grey, then there might be Custom Normals (below, under Geometry Data)

Per say, this is solved when cleared the custom normals like @StrayBillie says.
Now i cleared it and the smoothauto works when turned on like @Magnavis says.

As so:

2022-05-16 10_44_04-Ble_

So, ‘clear custom split’ … then it’s working. Thanks

Many, many thanks!