Sorry to hear about the trouble. Could you please check if you have verified your Adobe ID? If yes, please try signing out of XD and Adobe CC desktop app > Close CoreSync and all Adobe related process > Sign back on Adobe CC Desktop app and launch XD from there and try again to publish the link.
In case if it still doesn't work, could you please share a few more details like:
The version of XD.
Is this happening with a specific file or multiple files?
Did you start receiving this error after the recent update? If yes, could you please check if you are able to generate the link in the previous version of XD?
Could you please share your Adobe ID and the region through a DM, by clicking on my name?