The mode shown in the status screen is locked if:
- The switch on the lens is set to M which forces the lens in Manual Focus mode.
- The lens is a Manual-Focus Only lens such as Samyang and some Zeiss lenses.
- The lens is damaged or improperly mounted so that the AF contacts do not work.
- The attached AF lens has no AF motor built-in and needs an AF motor from the camera, which the Nikon D3300 does not have. This is the case for AF lenses, while AF-S and AF-P lenses have a built-in focus motor.