Sorry for the delayed response. Could you please confirm if you are still facing the issue?
Try changing resolution at preferences from custom to use system settings and colors are perfect now. Edit >preferences >page display >resolution >use system settings
Would you mind sharing the version of the Acrobat Reader DC you are using? To check the version go to Help > About Acrobat and make sure you have the latest version 21.07.20099 (Win) , 21.07.20096 (Mac) installed. Go to Help > Check for updates.
Also try to logout of the application, reboot the computer once and relogin with the same Adobe ID and see if that works for you.
We will be waiting for your response. Once we've got that information from you, we can take a closer look.