Hi and thanks for reaching out. My name is William. I'm a Microsoft Windows Certified Professional and Systems Administrator. I'll be happy to help you out today.
Have you tried creating the required registry values? Follow this link, save the file, double-click it to import the Night light settings: https://1drv.ms/u/s!ApX1j7el8hb3hFUVTBZZ1u4ngB9...
Alternatively, you can create a new text file on your desktop > edit with Notepad > paste the following text into it:
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\CloudStore\Store\DefaultAccount\Current\default$windows.data.bluelightreduction.bluelightreductionstate]
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\CloudStore\Store\DefaultAccount\Current\default$windows.data.bluelightreduction.bluelightreductionstate\windows.data.bluelightreduction.bluelightreductionstate]
"Data"=hex:43,42,01,00,0a,02,01,00,2a,06,bb,b0,b9,fb,05,2a,2b,0e,13,43,42,01,\
00,d0,0a,02,c6,14,e3,ff,b4,bd,d9,ef,a4,eb,01,00,00,00,00
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\CloudStore\Store\DefaultAccount\Current\default$windows.data.bluelightreduction.settings\windows.data.bluelightreduction.settings]
"Data"=hex:43,42,01,00,0a,02,01,00,2a,06,8a,b1,b9,fb,05,2a,2b,0e,21,43,42,01,\
00,ca,14,0e,15,00,ca,1e,0e,07,00,cf,28,d6,39,ca,32,0e,13,2e,25,00,ca,3c,0e,\
07,2e,05,00,00,00,00,00
Rename the file to append the .txt to .reg and double-click the file to import the settings.