Re: Bug/Glitch "Galactic Datacron Master" Achievement
if you actually started collecting these datacrons for this achievement back in 2011/2012 prior to legacy being introduced it is certainly possible that you can get into a bugged state as shown even with being completed in 2017
try sending an email to support@swtor.com and detail the username etc and link to this thread that acknowledges the bugged state you are finding yourself in with the achievement.
Hopefully CS will see it is an easy fix for this issue and will assist sorting this for you.
Let me know how you get on with this.
