How to solve 4k resolution FF xiv heavensward problem?

Hello. Someone knows how to resolve my problem. When I tried to play the expansion on the 4k resolution my mouse cursor doesn't come down to all the fullscream area. So I can't play the expansion on 4K resolution because the mouse don't move to all the area.

That's my PC specs:
GTX 1070
Intel(R) Core (TM) i7-4820K CPU @ 3.70 GHz
Memory: 32 GB RAM
Microsoft Windows 7 ultimate
MONITOR 28" LED 60HZ 4K UHD LU28E590DS/ZD SAMSUNG

Ty for the answers.

Maybe you should move this to technical