ReportProcessingException: The report definition is not valid. Details: The report definition has an invalid target namespace 'http://schemas.microsoft.com/sqlserver/reporting/2016/01/reportdefinition' which cannot be upgraded. code example
Example: The report definition has an invalid target namespace 'http://schemas.microsoft.com/SQLServer/reporting/reportdesigner'
<Report xmlns="http://schemas.microsoft.com/sqlserver/reporting/2008/01/reportdefinition" xmlns:rd="http://schemas.microsoft.com/SQLServer/reporting/reportdesigner">