Transaction refused due to risk model

The error “Transaction refused due to risk model” in Event Espresso is from the PayPal API, indicating that PayPal or the user's bank flagged the transaction based on their risk assessment criteria. This is often due to billing information discrepancies, similar to a failed address verification check (AVS). Users should check the transaction details in Event Espresso and, if needed, contact PayPal support or regenerate API keys if no error codes are visible.