topo map not showing on Garmin montana

[spud45]

I have downloaded several topo maps from GPS file depot to Garmin Base Camp with no problems.  I have then installed them on my Garmin Montana with Map Install.  If i look on my computer is shows all maps as being installed on the Montana. I have a map titled Idaho Topo and a land owner map called Topo Idaho   Problem when i go to Garmin Montana
map>select map.  Topo idaho does not show as being available to be selected.  If i remove "Idaho Topo",   the  "Topo Idaho" shows.  I am wondering if the problem is the mapset name.
When i use JaVaWa device manager is shows both of the above maps with the same mapset name.  Could this be causing issues with the Montana?  Thanks for the help.

[Seldom]

Map name (an 8 digit number unique to a tile) conflicts can cause tiles not to show up.  IIRC, if two tiles have the same 8 digit name neither will show up.  See what happens if you delete one of the maps with similar names.