Do you have this trophy showing up in the UI? "registered-on-askubuntu"? Did you restore your home directory after re-installing perhaps?
2013-02-27 23:30:23+0000 [-] Accomplishing: ubuntu-community/registered-on-askubuntu
2013-02-27 23:30:23+0000 [-] Not overwriting /home/rachi/.local/share/accomplishments/trophies/ubuntu-community/registered-on-askubuntu.trophy as it already exists.
Do you have this trophy showing up in the UI? "registered- on-askubuntu" ? Did you restore your home directory after re-installing perhaps?
2013-02-27 23:30:23+0000 [-] Accomplishing: ubuntu- community/ registered- on-askubuntu .local/ share/accomplis hments/ trophies/ ubuntu- community/ registered- on-askubuntu. trophy as it already exists.
2013-02-27 23:30:23+0000 [-] Not overwriting /home/rachi/