Sony alpha 7 R IV Instruction Manual page 186

Note
[Focus Area] is locked to [Wide] in the following situations:
[Intelligent Auto]
The focus area may not light up during continuous shooting or when the shutter button is pressed all the way down at once.
When the mode dial is set to
When [Subject Detection] for [Face/Eye AF Set.] is set to [Animal], [Tracking] cannot be selected as the [Focus Area].
Related Topic
Touch Operation
Adjusting the focus area settings to the camera's orientation (horizontal/vertical) (Switch V/H AF Area)
Registering the current focus area (AF Area Registration) (still image)
(Movie) or or during movie shooting, [Tracking] cannot be selected as the [Focus Area].
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