UNLOCKED htc cha cha 3g not working?

I recently bought an unlocked HTC cha cha off ebay. It says it was from at&t before it was unlocked but I put in my old sim card from ROGERS. I live in Canada and the phone was from the U.S. today I tried to use the 3G data but it wouldn't work. the 3g symbol wasn't where it usually is on android phones and when I tried to open a page it would say "web page not available" I was thinking maybe its because its in canada or something? Please help anybody! Thanks!