I was getting the following error when trying to resolve a dependency:

Method not found: void .ResourceLoadingQuery.set_Instance(object)

Basic Info:

• Version with issue: 4.1.0.555618
• IDE: VS2019 16.0.4

• Platform Target Frameworks:
  • Android: 9.0 (Pie)
• Nuget Packages:
  Xamarin.Forms 4.1.0.555618,
  NETStandard.Library 2.0.3

Solution:

Make sure that your Xamarin Forms NuGet package is updated to the same version in every project, including any .NET Standard libraries

Check out the Xamarin Forms docs