Seem to have a problem with the screen not showing black and grey properly. When watching dark scenes in videos or using apps the top right of the screen is showing more inconsistant black levels then the rest of the screen. I would descripe it as backlight bleed but i would not expect it on an oled panel.
If i rotate the screen it moves to the bottom left so to me it seems like a panel fault.
This does sound like a Hardware issue. I suggest you contact HP Support in your region for service options
1) Click on this link - www.hp.com/contacthp/
2) Select your product type below.
3) Enter the serial of your device.
4) Select the country from the drop-down.
5) Select the chat or get phone number options based on your preferences.
6) Fill the web-form and proceed further.
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