Fatal: Cannot access a disposed object. Object name: 'SslStream'.

[goorkamateusz]

Fatal error on server:

|Fatal|<>c__DisplayClass174_0.<startReceiving>b__2:0|System.ObjectDisposedException: Cannot access a disposed object.
                           Object name: 'SslStream'.
                              at System.Net.Security.SslStream.<ThrowIfExceptional>g__ThrowExceptional|138_0(ExceptionDispatchInfo e)
                              at System.Net.Security.SslStream.EndRead(IAsyncResult asyncResult)
                              at WebSocketSharp.NetCore.Ext.<>c__DisplayClass59_0.<ReadBytesAsync>b__0(IAsyncResult ar)

Server: .NET 6,
Client: Unity 2021

I've not observed special circumstances to this crash. After this message sockets are closed.
It happens many times.