If your payback was earned before 30th November it will roll over to the next period and may not show in your payback until February.
If your payback was earned after 30th November it will show up in the next few days.
It's important that you choose your payback method for each payback period as your choice is removed after any current period is either paid or rolled over. So use the website to make your choice as it's a little difficult to find in the app.
Also your ability to make a choice will only be available after you have a payback amount showing in your account.