Work through these in order.
Open Profile in ZlipR and look at the Notifications row. If it says Off, tap it and allow notifications.
If tapping it takes you to your phone's Settings, it means notifications were turned down earlier and only Settings can turn them back on. Find ZlipR in the list and enable Notifications.
Opening ZlipR once after granting permission lets it register your phone. Until that happens there is nothing for us to send to.
Still stuck? Reply to any ZlipR notification or write to us from the app.