Power BI Incremental refresh duplicate issues

Hi, ramashish74 

You can see the official doc about troubleshoot incremental refresh, the error may cause by the Post dates have changed.

Detail: With a refresh operation, only data that has changed at the data source is refreshed in the dataset. As the data is divided by a date, it’s recommended post (transaction) dates are not changed.

If a date is changed accidentally, then two issues can occur: Users notice some totals changed in the historical data (that is not supposed to happen), or during a refresh an error is returned indicating a unique value is not in fact unique. For the latter, this can happen when the table with incremental refresh configured is used in a 1:N relationship with another table as the 1 side and should have unique values. When the data is changed (for a specific ID), that ID then appears in another partition and the engine will detect the value is not unique.

Did I answer your question? Please mark my reply as solution. Thank you very much.
If not, please feel free to ask me.

Best Regards,
Community Support Team _ Janey