Recovery guidance
What to do when Stripe returns transaction_not_allowed
What it means for the customer
The bank may have blocked the transaction type or the card may not be allowed for the subscription payment.
First recovery move
Ask the customer to use a different payment method or contact the issuer to allow the transaction.
Retry timing
Stripe treats transaction_not_allowed as a hard decline for billing retries, so recovery usually needs a new payment method or customer action.
Email angle
Explain that the bank did not permit this subscription charge and offer a secure way to switch payment methods.
What to avoid
Avoid retrying as if the issue were temporary funds. The restriction is more structural than timing-based.