| 4000 | Failure | Invalid data. Missed required input fields |
| 4001 | Failure | Payment card expired |
| 4009 | Failure | Insufficient funds |
| 4010 | Failure | Transaction limit exceeded. Try another card. |
| 4012 | Failure | Transaction amount limit exceeded. Try another card. |
| 4119 | Failure | Such order_id already exists in the system. |
| 4124 | Failure | Invalid currency. Please use: USD, UAH, EUR. |
| 4139 | Failure | Invalid transaction amount. |
| 4144 | Failure | Invalid card data |
| 4147 | Failure | 3-D Secure verification timeout |
| 4148 | Failure | Timeout |
| 4149 | Failure | Session expired |
| 4150 | Failure | Invalid operation |
| 4151 | Failure | Invalid input fields |
| 4152 | Failure | Invalid configuration. Please, contact technical support. |
| 4153 | Failure | Transaction rejected |
| 4154 | Failure | Transaction is rejected by anti-fraud |
| 4155 | Failure | Transaction was declined by blacklist |
| 4156 | Failure | Card not supported |
| 4157 | Failure | Authorization failed. Please, contact issuer bank |
| 4158 | Failure | Transaction rejected. Please, contact issuer bank |
| 4159 | Failure | Wrong OTP code. Please try again |
| 4160 | Failure | Failed to create transaction |
| 4161 | Failure | Transaction declined due to balance limit |