The cartridges manufactured prior to 2017 were universal, they did not have a -Z marking and would work in any region.
Your printer has been locked to the Z20 region, you *will* need the regionalization reset to correct this so the proper Z10 cartridges will work. The unmarked cartridges will also work, they are universal.
I will ask to have your case escalated. It may take a few days (maybe more since the weekend is here....) for the request to work its way through the system.