My S4 support LTE but doesn't show it ? (BELL CANADA)

I have my S4 that was brought to me from Dubai , official unlocked and support LTE ..
i put my BELL sim card in it (was using iphone5) it works fine but doesn't show LTE .. it only shows H+
so i called CS they told me it wont support it bcs the device isn't registered with BELL ? i don't get how is that disposable or related ?

thanks

What version of S4 did you get? i9505 or i337m?

Sent from my SGH-I337M using Tapatalk 4

GT-I9505

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Help guys ?