Hi Pattio . Do these steps below .
Restore Windows to a previous state using System Restore
System Restore can return your computer system files and programs to a time when everything was working fine, so we will try to use this Windows feature to get rid of Ukash lock screen. 1
Restart your computer, and then press and hold F8 during the initial startup to start your computer in safe mode with a Command prompt.
Use the arrow keys to select the Safe mode with a Command prompt option.
In the command prompt, type C:\windows\system32\rstrui.exe
, and then press ENTER
System Restore utility will open, and you’ll need to select a restore point previous to this infection.
Once you're done you should be able to login to windows in normal mode
Download these programs MALWAREBYTES ANTIMALWARE
and HITMAN PRO