AutoRest Generation throws error

[rbandi124]

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Error :
warning | output-folder path should be an absolute path
fatal | System.InvalidOperationException: The duration property of MaintenanceConfiguration ends with "Duration" but does not use the duration format to be generated as TimeSpan type. Add "format": "duration" with directive in autorest.md for the property if it's ISO 8601 format like P1DT2H59M59S. Add "x-ms-format": "duration-constant" if it's the constant format like 1.2:59:59.5000000. If the property does not conform to a TimeSpan format, please use "x-ms-client-name" to rename the property for the client.
at AutoRest.CSharp.Mgmt.Decorator.Transformer.FrameworkTypeUpdater.ValidateAndUpdate(CodeModel codeModel) in D:\a_work\1\s\autorest.csharp\src\AutoRest.CSharp\Mgmt\Decorator\Transformer\FrameworkTypeUpdater.cs:line 27
at AutoRest.CSharp.Mgmt.Decorator.CodeModelTransformer.TransformForMgmt(CodeModel codeModel) in D:\a_work\1\s\autorest.csharp\src\AutoRest.CSharp\Mgmt\Decorator\CodeModelTransformer.cs:line 43
at AutoRest.CSharp.AutoRest.Plugins.CSharpGen.ExecuteAsync(CodeModel codeModel) in D:\a_work\1\s\autorest.csharp\src\AutoRest.CSharp\Common\AutoRest\Plugins\CSharpGen.cs:line 51
at AutoRest.CSharp.AutoRest.Plugins.CSharpGen.Execute(IPluginCommunication autoRest) in D:\a_work\1\s\autorest.csharp\src\AutoRest.CSharp\Common\AutoRest\Plugins\CSharpGen.cs:line 128
at AutoRest.CSharp.AutoRest.Plugins.PluginProcessor.Start(IPluginCommunication autoRest) in D:\a_work\1\s\autorest.csharp\src\AutoRest.CSharp\Common\AutoRest\Plugins\PluginProcessor.cs:line 39
fatal | Process() cancelled due to failure
error | Error: Plugin csharpgen reported failure.
error | Autorest completed with an error. If you think the error message is unclear, or is a bug, please declare an issues at https://github.com/Azure/autorest/issues with the error message you are seeing.