Details to reproduce:
- Try to buy something online with your Monzo card.
- When you get to the 3D secure step, wait for the notification to appear on your phone.
- Tap on the notification.
The Monzo app opens, but the screen is blank. The only thing shown is a back button.
If you press the back button and go to your transaction history, you can find the pending transaction and approve it from there, but if you go via the notification it won’t work.