Hey, Joan from the product team at Curve.
Thanks for raising this problem "…doing some special transactions, i forgetting to switch back to my main source card in Curve app. And then, during my next card payment, my bank refusing it due to insufficient funds…”. We have been looking at it and there are many solutions mentioned here, really good brainstorming.
Summarising them and adding some more solutions as follows:
Back up source card. (pros) would solve the problem while back up card has funds (cons) once Curve gets a response back from the issuing bank “insufficient funds” it is not possible to send a new authorisation request message to another bank, it would require a double authorisation request on every transaction, so to make a hold of funds on two accounts given auth is successful on both. Does not solve the problem “doing some special transaction, i forget to switch back…”. Still a chance the back up card has no funds.
Select card for a one off purchase, then it selects back the primary one. (pros) solves the issue of “i forgetting to switch back to my main source card”. (cons) does not solve the issue of declines due to lack of funds.
Decline App Notification: instantly prompt in the app a notification with the reason of the decline “insufficient funds” and being able to select another card within the notification. Then attempt the payment a second time. (pros) solves the problem of switching back to the primary card (cons) it has to be attempted a second time the payment.
Low Balance on the selected card warning: When the balance of the selected card is low, push notification with option to select a secondary card. (pros) solves the issue of “during my next card payment, my bank refusing “. Prevents the issue before the payment. (cons) It depends on PSD2 implementation not yet done, so long term solution.
Please let me know what you think about each option, any preferences, any more ideas very welcome.
Many thanks for your collaboration