Black Border on new Wide Monitor (3440x1440) 1cm big Border on Left, Top and Right (small at Bottom)

[FreakeyPlays]

Hello,

I just bought a new Screen (the SAMSUNG Odyssey G5 C34G55TWWP 34") .
I have seen a working example in the local tech store, and there all the screens did not have any sort of border. However, when I connected my PC (an Intel i5-13600K and an Intel Arc 750), I got big black borders on the Left, Top and right of the screen. First, I checked the resolution and scale, but they were correctly set. I also checked it in the registry, and there was no mistake. Then I read through the manual for the Monitor. There was a text that said:

Blank spaces are found on all four sides of the screen when an HDMI or HDMI-DVI cable is connected to
the product and PC.
The blank spaces found on the screen have nothing to do with the product.
Blank spaces on the screen are caused by the PC or graphics card. To resolve the problem, adjust the
screen size in the HDMI or DVI settings for the graphics card.
If the graphics card settings menu does not have an option to adjust the screen size, update the
graphics card driver to the latest version.
(Please contact the graphics card or PC manufacturer for further details about how to adjust the screen
settings.)

I now can't find any way to configure my borders with Intel Arc Control, and I am not able to change it in any way.

Could anyone please tell me how to fix this issue?

Thanks!!!