Unlike credit card disputes, all direct debit disputes are final and no appeal procedure is possible in Stripe.
There are two main types of dispute:
Insufficient funds.
Disputed payment by your customer or your bank.
In both cases, the pre-authorized payment must be cancelled on the invoice whose payment has been refused.
Go to the invoice on Plannit and Cancel pre-authorized payment on this invoice.
Modify this invoice by adding the fees charged by the bank so that your customer can reimburse them to you.
Resend the invoice to your customer so your customer can pay this invoice and re-enroll in pre-authorized payments.
Important
As Plannit has been debited directly from its account for rejecting your customer's payment, you will be invoiced by Plannit for the amount of the original payment plus the fee charged by the bank as a refund, which you can recharge to your customer.