tldr; Turning auto brightness off and setting brightness to the lowest might work.
I have been using the Exynos model for past two years. About a month ago or so the device first exhibited screen flickering issue all of a sudden. Green bars, black screen area, sort of animated and laggy. For the time being, only immediate lock-unlock attempts were causing the screen flickering (meaning, when I unlocked immediately after locking the device, the screen was causing trouble). I left it as it was and just kept avoiding immediate unlocking. Anyhow, after maybe a couple of weeks, out of nowhere the screen appeared to be flickering permanently and the device was rendered totally unusable. I tried doing some troubleshooting, factory reset, odin flash, etc. and none of them worked. Could not visit a service center in this lockdown situation.
Later, I figured that in my case, the screen is working at a very low brightness and partially working at full brightness but not working at all in between. It's just 90% black, 10% green and such. For about a week, I have been using it at a low (i.e. 5% to 10%) brightness. Left the auto brightness, always on display, and screen-on iris recognition settings turned off. I use Bixby or Google Assistant to set the brightness if I can't see the screen. With these setup, it's working for now. As of the software, I am on the latest firmware (May 2020 security patch).
From my observation, the issue had something to do with heating. I am not certain but I feel like the issue occurs more frequently if the device is used for prolonged period and heated up due to gaming or mobile data usage. I would suggest anyone who is stuck during this time before you can repair, should your device work at a low brightness then clean up the phone, get rid of unnecessary apps, games and reduce/avoid long usage that cause heating. Also leave the medium power saving mode on as it limits the CPU usage which supposedly help reducing the heating as well. Do not use night mode, gray wallpapers, etc. Use light or colorful backgrounds, apps, etc.
Thanks. Stay home and safe.
My first time posting- I've had the same issue for about two weeks. Had a repair person come and try and fix it, and diagnostic tools only picked up heavy ram usage.
Issue persisted, so had them come back out today and seeing the issue (video and shown live) they were able to replace the screen and battery - which at the moment appears to have corrected things.
Phone has stopped getting as warm too.
i am also facing this issue from 2 days. I have been using s9 for the past 1.5 years without any issue until now.
since so many people are fasing this issue i guess samsung should look into this issue seriously, and provide some resolution
My phone has the same issue, after some usage it heats up and turns light green with black flickering lines. My phone was bought within one year so as the warranty is still valid, i think i can get the components replaced?
It works (OLED SAVER) ! here is the settings after you enable it
-set you your screen to WQHD+
-Screen Mode: Adaptive Display
-use Pixel Filtering (it would look pixelated if your screen is in FHD)
-Basic Physical Brightness 255
Mine just looks the same as before.
The Green tint and flickering is gone, Hope it will last
Using S9 Plus Exynos (problem started after the update of android 10)
Hope it works for you too.
Yes it will really work but that did not fix the actual problem... and also, few times that OLED Saver will crash and your screen will go black. You have to know how to adjust your screen brightness while the screen is BLACK.