Question Samsung Galaxy A51 - display brightness problem


Good evening! I've owned a Samsung Galaxy A51 since March 2021. It's worked well, I can't say. It currently has the latest update: Android 11, One UI 3.1, update March 1, 2022. For a few days I noticed that it does the following problem sometimes and it didn't before. I have adjustable brightness to save battery. At low light level, low screen brightness, at high light level, higher screen brightness. But now, if I'm outside and want to unlock the phone, the fingerprint area appears and the display is lit at a higher level of light, but once it's unlocked by putting the fingerprint, I can't see the desktop anymore. The icons are barely visible no matter what position I rotate it. I can lock it and unlock it again, but it does the same thing multiple times. And it's not a problem that it's a sunny day and his light is set to maximum and it has to be held at a certain angle. There can be days without sun and it does the same, and if I look at the brightness, the ball is at the minimum on the blue. It's curious that if I move my hand towards the camera, it launches sensors (so the brightness of the display should be reduced at that moment), the level rises somewhat (which is much below the minimum that the AMOLED display can display) but it doesn't stay that way for long, as I move my hand away from the sensor, how the light level decreases again instead of increasing. It's not normal. I have glass foil, it's clean. I have never experienced anything like this before. Internally I have not seen this problem yet. Do you know something that could be? Any bug after the last update? A hardware problem? The idea is that if it doesn't always do the job, so if the seller can't see it and neither can the service person, I send it for nothing so they'll give it to me the same way I send it. The only way to get rid of this nonsense is either when the display lights up a bit more, to manually pull the strip with the light, or to deactivate and then re-activate the phase with the adaptive light.