International data on Unlimited Premium

Why was I charged for international data after switching to $0 plan? Another bait-and-switch by Xfinity Mobile? 

I switched one line from "Unlimited Intro" to "Unlimited Premium" because "Unlimited Premium" was described as  

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    Int'l talk, text, and data in 215+ destinations     $0.00 

    Service with unlimited talk and text  

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However, after switching, there were still international data charges (the country is included in the 215+ destinations), and the description of "Unlimited Premium" now reads: 

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    Service with unlimited talk and text              Included 

    Service while outside the US                         $xxx.xx  

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