so i bought a gs4 lte from at&t on ebay, unlocked it, and now i put my telus sim from my existing telus plan into the gs4. texting and calling works fine, but i can't manage to get the data working. is it because the bands aren't compatible? if they aren't can anyone suggest any canadian carriers compatible with the at&t galaxy s4?

ps, i also changed the apn settings and everything on the telus site and it still didn't work is it because my current plan was with iphone 4 and it didn't use lte?