Thanks for your reply
here is the event log results
Service cannot be started. Microsoft.ReportingServices.Diagnostics.Utilities.InternalCatalogException: An internal error occurred on the report server. See the error log for more details.
at Microsoft.ReportingServices.Library.ServiceAppDomainController.Start()
at Microsoft.ReportingServices.NTService.ReportService.OnStart(String[] args)
at System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(Object state)
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