How to debug an SLN solution in Visual Studio 2019 for Hololens

I am new to Visual Studio. I am trying out the Azure Spatial Anchor programs in Unity and have successfully deployed the application to Hololens. But I am not able to debug the application. If i set a debug point in one of the C sharp scripts, then toggle to the SLN solution which is a seperate VS 2019 session. Follow the below instructions: https://docs.microsoft.com/en-us/visualstudio/debugger/debug-installed-app-package?view=vs-2019

I get the following error: 'failed to launch remote debugger with the following error:'command failed: 0x80070490''

The debugger never stops at any of the breakpoints in the script. Could you please point me in the right direction?

Thanks, M