The first thing I would do with the Droid Turbo 2 that won't connect to 4G is to get another Sim card. It could be the card you have is bad. They are free at any corporate Verizon Wireless store. Hope this helps you out.
We definitely want to ensure your getting the most out of your services while in Puerto Rico! Lets take a closer look. If not completed yet, I do suggest power cycling the device as this can ensure the device picks up on the new network. When traveling international, its one of the first things I complete. This will kick the device to properly connect. If you've already completed this, I would ensure that your data roaming access is on. ( Settings > Data Usage > Menu> Cellular Network> Data Roaming Access )
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