IPhone 5 is 3g only. It will not give 4g service. Your goody bag is 4g but in your phone it will give service up to 3g .
Try this to improve things
IOS NETWORK RESET.
Follow the steps below to resolve this issue.
Settings > General > Reset > Reset Network Settings (and then confirm this again), This will reboot your handset. Now you will be connected.
.Check your phone settings:http://giff.ly/iphonesettings
Check your Do Not Disturb settings: Tap Settings > Do Not Disturb.
Check for any blocked phone numbers: Tap Settings > Phone > Blocked.
See if Call Forwarding is turned on: Tap Settings > Phone > Call Forwarding.
Ensure that your software is up to date:
Check for a carrier settings update.
Check for an iOS software update.
Note: Some updates may require a Wi-Fi connection and a battery charger.
Clean and reseat the SIM card.
PHONE RESET PROCESS.
To perform the reset.
1. Open iTunes
2. Connect your USB cable to the computer, NOT to your device yet.
3. Power Off your device, and be sure that it is Off.
4. Press the home and hold it.
5. Connect the USB cable to your phone. You will see a iTunes logo on your device, you can release the home button.
6. Do a recovery via iTunes. iTunes will now recover the phone.
If it doesn't work the first time, try again.
Try to make or receive calls in another location.
Attempt to isolate to one network band:
If you're having the issue on LTE, disable LTE, if possible, and try again.
If you're having the issue on 3G/4G, disable 3G/4G, if possible, and try again.