This GET endpoint is used to retrieve the pay-in history for a user with the specified token.
You can use this endpoint to view all pay-ins initiated for a user, including the payin_token, source_token, destination_token, amounts, and current status.
To use this endpoint, you need to provide the user token in the URL Path.
The response will include a JSON array of pay-in transactions for the specified user, with each transaction including details such as the pay-in token, amounts, currencies, fees, status, any required_action, and the partner network_response.