I actually use Gocardless for payments in my app. I have this API call and workflow:
Create a billing request (id of the new paiement)
Create paiement link
The workflow is :
So, I open the payment I previously created, but how can I know if the payment was successful or failed since I’m on another page?
I’m not sure how gocardless works, you’ll need to read their documentation.
However I’ll give you an example of how stripe works so you can know what to look for in gocardless docs.
Set a redirect after success URL in payment processor dashboard & after redirect your URL will have a SuccessID in url params. (If gocardless offers this make it your last possible option)
Webhooks (gocardless does offer event webhooks from my quick Google search) setup a backend public workflow API in bubble and give it to gocardless to respond to on success of a payment.
As a protection I tend to have once a day all accounts marked active in my database cross check my payment provider for active subscriptions to ensure nothing falls through cracks.
Yes, i will use the webhooks thanks a lot Chris 
