Check if you are filing for the same tax period that you've already filed+paid. Perhaps Taxumo is prompting you to file for a different tax period? You can check what you filed previously by going to your Past Filings.

You may not have completed the process in your previous filing. Similar to the above item, you can check by looking at the Past Filings and see whether the forms you previously filed are already in "In Progress" or "Completed" status.

If you entered income/expense/withheld taxes AFTER filing the form, Taxumo will recompute your form and see if you have to file an amendment. In this case, the form you're being asked to file again would already be an amendment. Just file as normal and we'll take care of making sure this is submitted properly.

You may have a different Alphanumeric Tax Code in your profile versus what you filed previously. For example, if you filed a non-8% Income Tax Filing in Q1 but your profile now indicates the 8% Tax Filing ATC, then Taxumo will see this as you haven't filed anything yet. To remedy this, make sure to select the ATC that matches what you filed previously. You can read more about that here.
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