During the implementation phase, you may encounter the "INVALID AMOUNT" error message. This message is typically returned when there is an issue with the Blowfish key or the encryption method being used.
The "INVALID AMOUNT" error message is generally triggered when an incorrect Blowfish key or an incorrect encryption method is applied. The "amount" is the first field that the Paygate processes in a transaction. Therefore, if an incorrect key or an incorrect encryption method is used, the Paygate cannot properly decrypt and interpret this field, leading to the aforementioned error message.
To resolve this issue, you should follow these steps:
Check the Blowfish Key: Make sure that you are using the correct Blowfish key for your transactions. An incorrect key can result in failed encryption and, therefore, failed data transmission.
Check the Encryption Method: It is important to use the correct encryption method. Ensure you are using Blowfish ECB (or AES, if previously activated on the MerchantID by us).
You can find detailed instructions on the correct use of the Blowfish key and the appropriate encryption method in our online documentation.
If you continue to receive the "INVALID AMOUNT" error message despite correctly applying the Blowfish key and the encryption method, our Merchant Services Team is happy to assist you further.