I'm so sorry you're having trouble. Let's see if we can get your issue resolved.
To restore your Just Ahead purchases:
1) Open Just Ahead
2) Tap on Find a Guide
3) Tap on Manage Purchases (note: you'll have to scroll down to find the button)
4) Tap the Restore button
5) You will be prompted for your Apple or Google password, enter it
6) After a few seconds any guides you have purchased from Apple or Google will appear on the screen
Once your purchases are restored you can now download and play your guides:
1) Tap the back button to return to the main screen
2) Tap Play a Guide, here you'll see a list of guides installed on your phone. To open the guide tap on the guide and follow the directions.
3) If the guide is not there Tap on Find a Guide, then tap on the guide you want to download, then either purchase the guide by tapping on the price or download the sample by pressing download sample.