Yeah there are basically two versions of the GSM LTE RAZR HD - one supports 700 / 1700 / 2100 and I think is only available in Canada, whilst the other version supports 800 / 1800 / 2600, and is available in Lat Am and Europe.
Sounds like you have the second version, which as rafjak says, will not work with either T-Mobile or AT&T LTE
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