Goods of EU origin need not be reported in the CBAM Registry
Only goods that are under the EU regulation on a Carbon Border Adjustment Mechanism are to be reported in the CBAM Transitional Registry. For example, goods of EU origin need not be reported.
When you declare CBAM goods that according to the general rules of origin originate in an EU country, you should select “EU – European Union” as the code of the country of origin in your import clearance. The country codes of EU member states are not to be used.
How to correct a customs declaration that is submitted incorrectly
If you have used the code of some other country of origin in declaring goods of EU origin, you can ask Customs to replace it with the “EU” code. Instructions for making an amendment request are available on the Customs website here: Amendment of a declaration.
After Customs has processed your amendment request and your declaration is corrected, you can edit the report you submitted to the CBAM Transitional Registry. If the report concerns only goods for which emissions need not be reported, you can delete it as unnecessary. Otherwise, you can correct the information in your report. You can however delete the report and correct it only after you have a decision from Customs on the correction of the customs clearance.
More information is available here: Carbon Border Adjustment Mechanism