@angelaloceo
I've done the same as you have, I've used Garmin Express to update a nuvi 765 and it seems that the Canada & Mexico map (Part of the N.America maps) is NOT updating.
You could call Garmin ,but from my experience they are not motivated to help with older devices.
Download and copy this Canada & Mexico map to the Garmin folder on the 32 GB SD card you have

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Your SD card should similar to this.
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