The tax file number is invalid.
This means that the tax number you have entered is incorrect and there are two issues that would cause this error to appear, they are:
- The TFN is the incorrect character length (must contain between 8-9 characters).
- The TFN does not meet the ATO standards.
We recommend you follow the Tax File Declaration article, and update your entered TFN so that it meets the ATO's standards. If your TFN does not meet the ATO standards, we recommend contacting the ATO to verify your TFN.