error 204

In PRODUCTION mode, if your buyer gets an error message such as:

An error occurred during the payment request, please make sure that the posted parameters match the ones specified in the documentation.

It becomes impossible to make the payment and the transaction is definitively lost.

You will receive an email notification containing the form that the gateway was unable to process and the value of the invalid field.

We invite you to check the following reason(s) to resolve the issue:

The algorithm used for signature computation does not correspond to the algorithm defined in your shop settings.

The signature algorithm is defined in your Expert Back Office via Settings > Shops > Keys tab > Security of data exchange.

SHA-1 orHMAC-SHA-256

For signature computation, make sure that you apply the same algorithm as the one defined in your Expert Back Office.