Null reference when getting top tracks by tag

[yuans-dev]

await Client.Tag.GetTopTracksAsync(Tag, page: 1, Results); where "Tag" is a string and "Results" is an integer, throws
"System.NullReferenceException in IF.Lastfm.Core.dll
Object reference not set to an instance of an object."

LastFm Client is properly instantiated.

[burak-ozenc]

I checked and debugged this issue but I did not understand why it is not validating. But Tag/GetTopTracksCommand/HandleResponse selecting an invalid token -- selecting "toptracks" instead of "tracks".