If the Jetpack displays "No battery" then it rules out the external power supply as the cause. It means there is an issue with the battery or the electro-mechanical connection points between the battery and the Jetpack. Removing and reinstalling the battery is often enough to fix it, but if not then lick you finger, rub it across the battery terminals and then polish/dry the terminals with your shirt tail. Do the same with the little connectors in the Jetpack where the battery mates taking care not to move them sideways--they push toward the Jetpack the way the battery is inserted. It might be necessary to repeat the whole process a couple times.
If you need additional information, please provide the model number of your Jetpack.
Diane, we want to make sure you have a working Jetpack. We will provide some troubleshooting assistance. We might need to have you do a factory reset on your Jetpack. Can you provide the make and model of the device?
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