If the issues you've purchased are not in your issues list in the app, first make sure you're on the same iTunes account you originally purchased the issues with. If so, hit the “Library” button in the menu bar, which should bring up a "Missing Issues?" button at the top left of the screen. Select "Restore" to re-download all issues you're entitled to. If the restore all function is not working, please make sure to verify that you have in app purchases enabled. Go to “Settings” then “Restrictions” then check to make sure that in app purchases are enabled. If they are not enabled, please enable them and repeat the restore all procedure.