Question Issue with display of dark elements on AOC AG273QZ monitor ?

[EdenPrime]

Hello,
I have an issue with my AOC AG273QZ monitor. When it needs to display something dark, very large pixels and halo appear.

Examples
Picture example on a game menu in 2560x1440 on the AOC AG273QZ :
https://freeimage.host/i/HV54jv2
Picture example on a game menu in 4K on an another monitor, same cable connected on the same graphic card connector:
https://freeimage.host/i/HV5rQ1f

What I have tested

• I tried to play with the screen settings like HDR, contrast, gamma, overdrive, etc. I also tried to edit those settings directly on the Nvidia software and windows, but I wasn't able to improve anything.

• I tried many cables (HDMI, DisplayPort). The pictures have been taken using Lindy DisplayPort version 1.4 going up to 8K@60Hz on 7680 x 4320 pixels.

• I sent it for repair but they found no issue and returned it without doing anything to it.

Any idea?

Thanks for your help