I can't set my screen to 1920x1080.

You should have something like this: "C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static\CLI.exe" Start Wizard
if you launch this you should get a start of the configuration menu... Then go to "Advanced"

or ... Catalyst is not your display driver...???

Yes, there is a menu for Catalyst,

you follow the same path as before

then "Advanced settings" ... tab card, "List all modes" 

and instead of going to card, go to the tab "Control Catalyst...." then on the page, down, there is "ATI Catalyst Control Center" you click on it. new window.

-- On the top left "Graphic" click on the small triangle, choose "Desktop and Display" you see your Monitor and in the bottom line, a screen with a small triangle next to it..click--->configure ..New window, if you uncheck the box, you can set your custom display...
Otherwise, you check the EDID box and normally it will read the definition of your screen transmitted by the EDID data of your screen panel.. (if it is connected..??)

Otherwise, you also have On the top left "Graphic" click on the small triangle, choose "Desktop Properties" and there, you can also set the parameters of your screen resolution..

There are still quite a few things to try..

It would be good to see
if you have another driver
available
for your PC
I found this
http://support.amd.com/fr-fr/download/desktop?os=Windows+10+-+64
I think you are on 64 bits
get the Radeon Software
that should allow you
to restore
your display to 1900
after a restart, of course
a PC is like a car?
if we don’t maintain it
one beautiful morning it won’t start anymore

I managed to fix my problem! I installed the AMDR Catalyst Control Center and looked for the latest updates, it made me reinstall everything but it still didn't work, then I foolishly switched my computer back to 1600x1200 and then back to 1920x1080 and now it works! It's all beautiful, thank you very much for helping me!

Hello

It’s probably a graphics driver update

that didn’t work properly

Go to the device manager
Go to properties
of your graphics card / driver
and click
on (roll back to the previous version)

Restart .......
and see what happens

--
A PC is like a car? If you don’t maintain it
one fine morning it won’t start anymore

OK, nice perseverance...!

and the result at the end...

But still, Windows 10... it's not really that great..

Well, I think it should be marked as Resolved...?

Hello,

What model is the screen??

If your screen is a "generic plug and play," it means that the precise model of your screen is not recognized... so it is a generic model that has been adopted.
You need to get your screen model recognized by Windows... didn't you get a CD with this screen..?

In Control Panel\All Control Panel Items\Display\Screen Resolution, there should be the model of your screen (display) and below you can modify the resolution (width x height)

Then "Advanced settings"... tab card, "List all modes" and there, you can choose the display mode of your screen as the card should do
like 1920x1080 at 60Hz 16 bits or 32 bits...