Hi @poojamudgal
As far as I know, in Adobe target when you clone or migrate activities from one account or environment to another, the historical performance data (reporting data) doesn't come directly. It's always start with new data.
And also there is no built in functionality which allows this migration.
Though there are few options you can try
1) Export current data:
Before migration, you can export the current activities report data in .CSV format at below link, there are the steps download the data https://experienceleague.adobe.com/en/docs/target/using/reports/settings/downloading-data-in-csv-file
The download options has some caveats. please consider those while downloading reports.
this way you can compare the previous data with new environment where Adobe target up and running with new activities.
2) Use Adobe Target Reporting API
Retrieve performance report data for the activity with all metadata https://developer.adobe.com/target/administer/admin-api/#tag/Reports
3) A4T data - In case in the current setup you're working with A4T (Analytics for Target) setup, and also has an access to AEP ( Adobe Experience Platform) then seems you can pull this historical data.
and last option contact your Adobe Account Team / customer support team for more info.
Hope this helps.