Hi Bill...that shows really how poor the error messages are. Am a bit surprised because TomTom seems to have some responsibility somewhere? I would have thought the full Map library would have loaded easily...its somewhat alluded to by the Maptool you use. We learn.......
The update is to the EIRcode database only not the Nissan/TomTom maps. Heaven knows when the regional maps update and that "might" incorporate EIRcodes. That applies to UK Post Codes as well. I expect some money has to change hands somewhere?
Points of Interest (POI)
I found a US Nissan Connect User Manual...luck. Do you have as pic. If so equipped.... thats how you can set your own place codes. And since you have cleared out memory they should work
Nissan 2019 Connect Box page 6-1 (US Version)
SATNAV / EIRCODES