Serilog not working from configuration in asp.net core 2.2 API

Your config is for RollingFile but your package list says Serilog.Sinks.File. These are different. You need to add the Serilog.Sinks.RollingFile package and it should start working.

If you want to use the File sink (which, as @Kirk mentioned in the comments, is the recommended option now) then you need to change the settings to

"WriteTo": [
    {
        "Name": "File",
        "Args": {
            "path": "C:\\test.txt",
            "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.ffff}|{TenantName}|{RequestId}|{SourceContext}|{Level:u3}|{Message:lj}{NewLine}{Exception}",
            "restrictedToMinimumLevel": "Information"
        }
    }

NOTE

The pathFormat should be path for the File sink

See the Serilog File Sink Documentation