Azure function with .net core nuget throwing startup issues

Hello,
I have a working azure function which is recently updated to .net framework 4.7 however i am running it with .net standard sdk as it cannot yet go fully core. however on startup i continue to get this error.

Could not load file or assembly 'Microsoft.Extensions.DependencyInjection.Abstractions, Version=2.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60' or one of its dependencies. The system cannot find the file specified.

I have no idea really what is causing this. This nuget is also not directly used in my function and there are no traces.

What could be causing this.

I am using Microsoft.ASP.NET.Core 2.1.6 version