Package Failed with VS2019

Error Log:

• UATHelper: Packaging (Windows (64-bit)): CSC : warning CS1685: The predefined type 'System.Runtime.CompilerServices.ExtensionAttribute' is defined in multiple assemblies in the global alias; using definition from 'c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.6.2\mscorlib.dll' [F:\UnrealEngine\UnrealEngine\Engine\Sou
• rce\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,68): error CS1525: Invalid expression term '[' [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,69): error CS1003: Syntax error, ':' expected [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,82): error CS1002: ; expected [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,82): error CS1525: Invalid expression term ']' [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,84): error CS1525: Invalid expression term '.' [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\FileLockInfo.cs(21,85): error CS1003: Syntax error, ':' expected [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Framework\Gauntlet.TestExecutor.cs(360,15): error CS0136: A local variable named 'StartTime' cannot be declared in this scope because it would give a different meaning to 'StartTime', which is already used in a 'parent or current' scope to denote something else [F:\UnrealEngine\UnrealEngine\Engine\Source\Progra
• ms\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Unreal\Base\Gauntlet.UnrealSession.cs(864,27): error CS1525: Invalid expression term '.' [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Unreal\Base\Gauntlet.UnrealSession.cs(864,28): error CS1003: Syntax error, ':' expected [F:\UnrealEngine\UnrealEngine\Engine\Source\Programs\AutomationTool\Gauntlet\Gauntlet.Automation.csproj]
• UATHelper: Packaging (Windows (64-bit)): Project file contains ToolsVersion="12.0". This toolset may be unknown or missing, in which case you may be able to resolve this by installing the appropriate version of MSBuild, or the build may have been forced to a particular ToolsVersion for policy reasons. Treating the project as if it had ToolsVersion="4.
• 0". For more information, please see [Link Removed].
• UATHelper: Packaging (Windows (64-bit)): HTML5.Automation -> F:\UnrealEngine\UnrealEngine\Engine\Binaries\DotNET\AutomationScripts\HTML5\HTML5.Automation.dll
• UATHelper: Packaging (Windows (64-bit)): Project file contains ToolsVersion="12.0". This toolset may be unknown or missing, in which case you may be able to resolve this by installing the appropriate version of MSBuild, or the build may have been forced to a particular ToolsVersion for policy reasons. Treating the project as if it had ToolsVersion="4.
• 0". For more information, please see [Link Removed].