Transaction not returning errors with preauthorization

[staffler-xyz]

I am trying to force an error code in test mode (for example 50501). I am using a preauthorization (which works) and then a transaction (which fails as expected).

However, the gem only returns the error "Paymill::APIError: Preauthorization has already been used" instead of the actual error code.

Is this just a problem of the test environment?