Problem adding credit card

Hello, For several weeks I have been stuck on a request that does not work. Let me explain in more detail: Creation of the MangoPay customer account (OK) Creation and allocation of your wallet (OK) Creation of a credit card (No error, I have a “success” message and no card is visible) I explain the credit card problem in more detail: I send a request to the Mangopay server “ClientId/cardregistrations” I got a success : “……..”Currency”:”EUR”,”Status”:”CREATED”}” I use the link (approval) to send the credit card information to get the card token (I get success because the server sends the token back to me) I send the token to Mangopay so that it validates (“….$client_id/cardregistrations/$CardId/”) the addition of the bank card (I get a JSON response from the mangopay server “Success”) Logically I should have the credit card that was added to the customer’s account in question, so I’ll look on the dashboard (sandbox) to check that everything went well and I don’t see any credit card added anywhere. So I decide to do a server-side check without going through the dashboard and when I search for a map via the token and a request “….ClientId/cardregistrations/CardRegistrationId/” and I get that no resources are found. So I asked the MangoPay technical service by phone to find help and asked me to post my concern here. Looking forward to your return. Thanks in advance.