Editing gpx traces

Hello every body

i m still new in this community.I have made with my garmin GPS a trace with some points.so when i m in JOSM.I open my gpx file et i download the appropriate data from OSM database.The problem is that i can’t edit my trace gpx.I want to change the position of some points but i can not select them as a result my trace is fixed,I don t know why. i m not interested in the trace but only in the points.Help
thanks a lot

try www.routeconverter.de, prune or viking to edit your GPX-file before you load it into JOSM.

Or did you already try the edit-gpx-plugin of JOSM? can you move gps-points there?