When making a payment by credit card via PayPal, a popup opens: it is PayPal that initiates the 3D Secure authentication process.
Subsequently, it is the card-issuing bank that takes over and displays its 3D Secure interface in the same popup.
Once the bank has authenticated the cardholder (via SMS code, banking application, or other methods), it transmits the result to PayPal, which then resumes the payment process until its completion.
Origin of the problem
In certain cases, it may happen that the popup remains stuck or that the authentication fails. This generally arises from a temporary malfunction on the part of the issuing bank (maintenance, temporary service interruption, internal technical issue). Therefore, it is neither a defect of the module nor an issue on the shop's side, but rather a specific banking incident.
Why a simulation or another test is not helpful
A Sandbox simulation is not useful: the 3D Secure is simulated there, and it does not reflect the actual behavior of a bank.
Conducting a payment test with another credit card is also not relevant: the 3D Secure interface displayed depends on each bank, and therefore each test corresponds to a different environment.
What should be done in this case?
In this type of situation, the most effective course of action is to contact PayPal directly: PayPal is responsible for processing payments and possesses the necessary data to analyze the incident.
To facilitate their investigation, it is important to provide them with precise information, such as:
- the date and time of the payment attempt,
- if possible, the last four digits of the card in question.
In summary
The problem arises from a temporary malfunction on the issuing bank's side during the 3D Secure process. The module is not at fault. For any in-depth investigation, only PayPal is able to analyze and confirm the source of the problem.