My Win64 Project is failing with MS Build ' error MSB8007: The Platform for project '<my_project>.vcxproj' is invalid. Platform='Win64''

I'm attempting to build a UE5 project through Team City. My build fails on the .NET build step when attempting to build from the UE5.sln.

 error MSB8007: The Platform for project '<my_project>.vcxproj' is invalid. Platform='Win64' 

I know that the platform (Win64) is correct.

Is there any other reason that I might be getting this error?

Things I've tried

• Setting platform to 'x64'.
• Leaving Platform blank.
• Updating VS 2019.