jmapb
(Jmapb)
8
All I can advise you is to try downloading some of the maps from https://wiki.openstreetmap.org/wiki/OSM_Map_On_Garmin/Download and try to put them on the Garmin. If you’re having trouble, maybe contact Garmin for support. They intentionally designed their equipment to be compatible with 3rd-party maps and they should be able to help.