Are you still facing the issue? Is this a behavior with a particular PDF file or with all the PDFs? Please try to open a different file and check.
Please try to create a new test user profile with full admin rights or enable the root account in Mac and try using the application there and check.
If it still doesn't work, please share the file with us for testing so we can check it at our end?
Please try the following preference settings and check if that works for you Go to Edit (Windows), Adobe Acrobat Reader DC (Mac) > Preferences > Page Display > Select Use local Fonts > click OK , restart the application
You may also ask the user to repair the installation (For windows only) Go toHelp > Repair Installation.