Auto brightness and True Tone not working

True tone and auto brightness do not work on my device. As soon as you turn on automatic brightness, the brightness is set to 50 percent and does not change unless you change it manually again. True tone does not seem to make any color transition, it turns yellow when turned on, for example, the screen does not turn blue in a blue environment, it does not behave as it should. My screen is original second hand and I completed the repair with iOS 18. The sensor is part of the device itself, so I bought a new one thinking it might be defective, but there was no change. The socket on the motherboard looks clean.