Saving after Combing PDFs

Hi darrend95192276,

Update Acrobat DC to the latest version Release Notes | Adobe Acrobat, Reader & then try to replicate the issue.

In case the issue persist try the below solution :-

The default "Save As" dialog in Acrobat DC is different than the dialog that you've had in earlier releases of Acrobat, it also allows you to save to the cloud and previous locations you've saved files to. It is possible that when Acrobat tries to connect to "the cloud", it runs into problems. You may want to try to turn this feature off to see if that brings your save as dialog back: Open up Acrobat's preferences, then go to the "General" category and deselect "Show online storage when saving files":

Let me know how it goes.

Regards,
Aadesh