Hope you are doing well and sorry for the trouble.
Would you mind sharing the version of the Acrobat DC and the OS you are using? To check the version go to Help > About Acrobat and make sure you have the recent version 22.1.20117 (Win), 20112 (Mac) installed. Go to Help > Check for updates and reboot the computer once.
Is this an issue with PDF created from AutoCAD files or with other files as well? Please try to create the PDF from a Word or Excel file and check.
What is the workflow/steps you did to create the PDF from Auto CAD file? A small video recording of the steps you are doing and the error/issue you are experiencing would be very helpful.