We had a Xamarin 3 iOS application built using Telerik 2018 components and it was working fine until the recent update in iOS. However, after the iOS update to 15, Xamarin 3 iOS app started crashing. Then we updated our app to Xamarin 5 and were able to successfully compile and run it on an iOS 15 simulator. But the Telerik 2018 controls did not render on screen. So we upgraded Telerik control to 2021 version (trial), and now we are having following error which broke the compilation of the entire project.

you must add a reference to assembly 'netstandard version=2.0.0.0 xamarin

It seems that Telerik 2021 controls have a dependency on netstandard library which is either not supported or cannot be installed from NuGet. 

It would be great if you could help us to resolve this issue. This way we would recover our app from crashes, and purchase the latest updates for Telerik.