Maintenance for the week of December 8:
• [COMPLETE] ESO Store and Account System for maintenance – December 10, 9:00AM EST (14:00 UTC) - 12:00PM EST (17:00 UTC)
Might wanna test one or the other to see if that resolves the issue. I briefly recall getting an error similar to this at some point the other day in the midst of testing a bunch of other unrelated stuff, but I think it went away after a reloadUI.