Upgrade Creative Cloud

can you rollback your os upgrade?

if yes, do so.  then 

uninstall every cc app including preferences, https://helpx.adobe.com/creative-cloud/help/uninstall-remove-app.html

then uninstall the cc desktop app, again using the correct uninstaller, https://helpx.adobe.com/creative-cloud/help/uninstall-creative-cloud-desktop-app.html#sa_src=web-messaging

clean your computer of cc files per http://www.adobe.com/support/contact/cscleanertool.html

restart your computer (don't skip this)

then upgrade your os to the current 12.xx

install the cc desktop app and use it to install your cc programs.

if you can't rollback your os upgrade, can you upgrade to the current mac os?  

if yes, do so.  and then do the following:

if you can't, you can still try the following.  skip steps you're unable to do:

uninstall every cc app including preferences, https://helpx.adobe.com/creative-cloud/help/uninstall-remove-app.html

then uninstall the cc desktop app, again using the correct uninstaller, https://helpx.adobe.com/creative-cloud/help/uninstall-creative-cloud-desktop-app.html#sa_src=web-messaging

clean your computer of cc files per http://www.adobe.com/support/contact/cscleanertool.html

restart your computer (don't skip this)

reinstall the cc desktop app, https://creativecloud.adobe.com/apps/all/desktop?action=install&source=apps&productId=creative-cloud

if you're unable to download the cc desktop app at this stage, use the "alternative download links" at the bottom of the page at https://helpx.adobe.com/download-install/kb/creative-cloud-desktop-app-download.html

use the desktop app to install your cc programs/trials