Problem in Sandbox mode when test CardPayment

[LeandroArista]

When trying to use the CardPayment component from the Mercado Pago React SDK, I receive a 500 Internal Server Error when calling the card_issuers endpoint. This issue started recently — until yesterday everything worked fine using the same test credentials and test cards.

Request
GET https://api.mercadopago.com/v1/payment_methods/card_issuers?public_key=TEST-XXXXX&locale=es&js_version=2.56.1&referer=http%3A%2F%2Flocalhost%3A3000&bin=52873383&payment_method_id=debmaster&product_id=C85Q6TGS4G718CFJS27G

Response

{
  "message": "unknown error",
  "error": "internal_server_error",
  "status": 500,
  "cause": [
    "Error when calling payment method repository findAll: an error occurred while fetching data from payment method"
  ]
}

Steps to Reproduce

Implement Mercado Pago React SDK with the CardPayment component.

Use the following test card from official documentation:

5287 3383 1025 3304

Run checkout with test credentials.

The request to card_issuers fails with a 500 error.

Expected Behavior

The request should return the issuer information for the test card without errors, as it was working yesterday.

Actual Behavior

The request consistently fails with:

500 Internal Server Error

Message: unknown error

Environment

SDK: React SDK (CardPayment component)

API: https://api.mercadopago.com/v1/payment_methods/card_issuers

Credentials: Test credentials

Status: Worked until yesterday, now failing