As the repo says, [TLSharp](https://github.com/sochix/TLSharp) is no longer maintained: the last compatible dotnet version is 4. Consider moving to [WTelegramClient](https://github.com/wiz0u/WelegramClient)
As the repo says, TLSharp is no longer maintained: the last compatible dotnet version is 4.
Consider moving to WTelegramClient