JOSM uploading "objects to modify" that were downloaded from HOT Project limits

This is my second contribution to OSM (actually HOT for a project in Tchad). The first edit was done using the iD editor triggered from within the OSM Tasking Manager and I had no problems with it but ..

my second contribution was done with JOSM and it contained the existing Project limits. When I did upload, I "had 5 objects to modify" in the Upload dialog (mainly duplicated data). Those objects were also indicated having errors (duplicated areas and nodes) in the validation dialog. I ignored the errors since they were not mine. Since I am new to the mapping in the OSM environment I am wondering if I should have done something differently.

I also noticed that when I used the iD editor, the Project identification was entered automatically such as "Chad, Kelo, #hotosm-task-772" but when I used the JOSM editor this information did not get included automatically. I guess I should have entered it manually in the "Provide a brief comment for the changes you are uploading" dialog ?

Many thanks for helping,