Please verify that none of the forms you are using are locked: TurboTax FAQ: Why does TurboTax say my forms are locked or haven't been finalized? If you are using any of these forms you won't be Netfile at this time until these forms get finalized by CRA and gets update within TurboTax for an accurate calculation.
If you are not using any locked forms, we suggest you to contact our Product support team. They have access to tools we don't have here in Community, like screenshare to investigate this issue for you.
Thank you for choosing TurboTax.