I got my auto-brightness shut off why does my phone keep dimming

Deago21 wrote:

Why does my phone keep dimming I have the auto brake shut off and I have everything that I’ve always told me to do but it’s still keeps dimming slowly

Settings and tap Accessibility -> Display & Text Size. Then, turn off the switch next to Auto-Brightness.

Settings -> Display & Brightness and tap Night Shift. Tap that switch to turn Night Shift off

Control Center-> press and hold the brightness slider. Then, tap the Night Shift button to toggle it off or on.

Settings -> Battery and make sure the switch next to Low Power Mode is off.

Settings > Accessibility -> Display & Text Size> Reduce White Point and check if turned off Reduce White Point.

Restart your iPhone if necessary and compare your results — restart, ie power off/on,

Restart your iPhone - Apple Support

There are two conditions that might cause the screen to dim, in addition to what leroydouglas posted:

1. It the phone gets too hot it will dim the screen to lower the phone’s temperature, as the screen is a huge generator of heat
2. There’s a feature called Attention Aware that will dim the screen when you aren’t looking directly at it - you can disabled this by going to Settings/Face ID & Passcode and turning it off.

In addition, the screen will dim a few seconds before the screen auto-locks, as a warning.