You don't. Sign into your Verizon wireless account and disable text messaging on your Jetpack. Then reset your Jetpack with the Restore Defaults button under the back cover to delete the messages.
I believe the Text messaging feature is something that is intended for another service provider. That feature has never worked well with Verizon. All you can do is view the messages anyways even if it did work.
I would be just as curious on how to retrieve a text if I saw a text alert on my jetpack. Depending on the exact jetpack model, there may be a way to view them. (Texts messages are only able to be received, not sent.) The maximum messages your device will store is 5 & your jetpack will delete the oldest message when a new message arrives on your device. You'll need to sign into the admin page for the jetpack to see the texts. Here is a link to get started: https://www.verizonwireless.com/support/knowledge-base-83898/ This link may not be your jetpack model, but the steps are the same for all jetpacks that have the text message alert feature.
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