Last week I received my Investor debit card, and in the excitement it didn’t cross my mind that I had a weekly Continuous Payment Authority (CPA) on my outgoing card, and therefore (along with it being Christmas) forgot to update my details.
Today it occurred to me that I hadn’t received my usual early Thursday morning notification, meaning I’d missed my payment window which has messed up my delivery slot. There was an email from the company (buried deep in my junk folder, helpfully) but it made me think:
The company had tried to take payment from my old card number, which had been rejected. Could 
Monzo look at either sending a notification stating a payment attempt had been rejected due to it being on an expired card, or, when activating a new card, identify that I have CPAs attaches to my card and remind me to update.
I’d actually prefer the former, upon reflection. It would be more flexible, and reactive (not place the onus on me to remember to proactively go off and change things in the background, which was the problem in the first place) and would also help with saved card details at places like Amazon/online shopping which I forget about for months until needed after a card change.
In short, please can Monzo look at continuing notifications on payments rejected from expired cards.