Hope you are doing well and sorry for the trouble. As described you can't see PDF images anymore.
Is this a behavior with a particular PDF file or with all the PDFs with images? Please try with a different PDF file and check.
What is the version of the Adobe Acrobat Reader DC you are using? To check the version go to Help > About Acrobat and make sure you have the recent version 21.11.20039 installed. go to Help > Check for updates and reboot the computer.
What happens when you try to view the PDF images? Do you get any error message? If yes, please share the screenshot of the same for a better understanding? Also a small video recording of the same will be very helpful.