1. Payment Authorization Failures
- Insufficient Funds: The customer’s account does not have enough balance to complete the transaction.
- Card Expired: The credit or debit card used has expired.
- Invalid Card Details: Incorrect card number, CVV, or expiry date entered.
- Bank Declined: The issuing bank rejects the transaction due to risk concerns or internal policies.
- Credit Limit Exceeded: The cardholder has reached their credit limit.
2. Technical and Connectivity Issues
- Gateway Timeout: The payment processor does not respond within the expected time.
- Network Issues: Poor internet connectivity between the merchant and payment gateway.
- System Downtime: The payment processor, acquiring bank, or issuing bank experiences downtime.
- API Errors: Incorrect API integration between the merchant and the payment gateway.
3. Security and Fraud Prevention Measures
- Suspicious Activity Detected: The transaction is flagged as fraudulent by the fraud detection system.
- Incorrect 3D Secure Authentication: Failure to enter the correct OTP (One-Time Password) or authentication details.
- High-Risk Country or IP Address: Transactions from certain locations may be blocked due to fraud risk.
- Mismatched Billing Information: The billing address provided does not match the one on file with the bank.
4. Merchant Configuration and Restrictions
- Payment Method Not Supported: The merchant does not accept a particular card or payment type.
- Transaction Limit Exceeded: The merchant has a limit on transaction amounts per purchase.
- Merchant Account Not Active: The merchant’s payment gateway account is inactive or suspended.
5. Regulatory and Compliance Issues
- Cross-Border Payment Restrictions: Some banks or regions restrict international transactions.
- KYC/AML Issues: The transaction is blocked due to Know Your Customer (KYC) or Anti-Money Laundering (AML) regulations.
- Invalid Currency Selection: The selected currency is not supported by the payment gateway
6. Customer Issues
- User Abandoned Checkout: The customer closes the payment page before completing the transaction.
- Session Expired: The payment session times out due to inactivity.
- Customer Entered Wrong OTP/PIN Multiple Times: The transaction is declined for security reasons.
