Power BI report server points to Old database when automatic refresh kicks in

Hi,Mithraveer .I am glad to help you.
Please try to clear the data source and credentials information in Power BI Dektop and reopen the pbix file that is causing the problem and remove the pbix file from your report server.
Restart Report Server Configuration Manager and re-upload the report from Desktop to your report server.
Take care to modify the Connection string in the report DataSource to make sure it points to the new Oracle database, not the old one.
Sometimes clearing the cache may solve the refresh issue, please try clearing your browser cache.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Carson Jian,
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