Hope you are doing well and sorry for the delay in response. I hope you would be able to fix it by now.
If the issue still exists, would you mind sharing the version of the Adobe Acrobat DC you are using? To check the version go to Help > About Acrobat and make sure you have the latest version 21.05.20048 installed. Go to Help > Check for Updates and reboot the computer once.
Is this a behavior with a particular PDF file or with all the PDFs? Please try with a different PDF file and check.
Please try to repair the installation (Win Only) Go to Help > Repair Installation and reboot the computer once and check if that helps.