Okay. So with that said, try this. Turn off the Wi-Fi on the device, and make sure the phone has it's mobile data turned on. What network do you see? Does the data service work?
Next, go to Settings > Cellular, and temporarily disable LTE. Do you have 3G or 1X service? Does the data service work?
Go ahead and turn on LTE and Wi-Fi at this point and confirm your findings.
You can also try going to Settings > General > Reset > Reset Network Settings, just to make sure the phone doesn't have anything wrong with it from that regard. You might need to re-connect to your Wi-Fi network after doing this, but this should force the phone to re-activate with Verizon.
To make sure your phone has the latest carrier profile, go to Settings > General > About while on Wi-Fi, and sit here for a few seconds. If you are prompted to update your Carrier settings, click OK to do so.
I would also make sure the iPhone 5S is on iOS 9.2. Newer Carrier settings will apply to newer versions of iOS.
Let me know if any of this helps.
Astreiff21, we appreciate your efforts thus far. We're stepping in to help. When did this issue start on her device? How many bars of reception does she have on the top status bar? Have you powered your device off/on since this issue started?
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