Error: CMN.ATO.GEN.DUPLICATE.ENTRY
Answer: This is ATO side validation.
This error triggers when the ATO rejects the return due to a return already lodged for a particular year for the TFN. In this case, please check the ATO portal to see if a return for the same year was lodge.
Other workaroun
Please try to remove the ABN from the return and attempt to lodge again. If you have attempted to relodge and still receive the error, please call the ATO, that is the fastest way and they can fix such issues online. If it didn't help - please let us know and we'll contact ATO tech team for them to investigate. Note that, it will take a week for them to response. ATO phone 13 72 86 Fast Key Code 3 1 2.