S2721DGFA, DP 1.4, RTX 3080, refresh rate issue

Hello,

I got a new display Dell S2721DGFA and I can't change the refresh rate from 59Hz to any higher. When I try to change to 120/144/165Hz, the display goes black and on screen pops up info "no DP signal coming from your device", then it turns on after that I don't have any other option than 59Hz, all the other options are gone. If I want to have another options to be back I need turn off pc,unplug  monitor from power then wait 1 minute and turn on pc but again. When I try change to 120/144/165Hz I got the same situation as above.

On an HDMI cable everything is ok. I can change to 144Hz without problems, except there's no G-Sync and no 165Hz.

I think i tried everything:
-I clear reinstall GPU and monitor drivers twice,

-I tried all my DP ports in my GPU,

-AMD FreeSync Premium Pro set to On in the S2721DGFA Menu

- Game,-G-Sync turned on in the Nvidia Control Panel- Manage 3D Settings.

I use 1.4 DP cable that comes with Dell monitor

My spec:

-RTX 3080 Asus Tuf
-AMD Ryzen 5600x

-MSI B550 Tomahawk

-16 GB RAM

-Seasonic FOCUS GX-750

Please help.What else can I do/try to fix this.I just want to use what I paid for.

Best regards