You don't need to unlock it, the One X from Rogers will work on Fido and Chatr out of the box.
(Proven by the fact that you can connect. If it as locked, it would never connect. The phone wouldn't let you.)
I have a feeling it's because Rogers hasn't enabled LTE on the Fido network yet. So my suggestion would be to disable LTE on your One X: Settings > Mobile Data > Network Modes > Select "GSM / WCDMA auto"
Edit: Beat by killathenoob :P
HTC One [UL / Stock JB 4.1.2]
HTC One X [LTE X325a / Retired]
Asus Transformer [TF101-B1-B60 / Retired]
HTC Desire [GSM A8182 / Retired]
HTC Hero [GSM Black / Retired]