BearerTokenConnection not working

I was trying to add comment using code into particular youtrackitem.
but it is giving 404 error. not sure what is correct api url

var youtrackConnection = new YouTrackSharp.BearerTokenConnection("https://xxxx.myjetbrains.com/youtrack/api/", "token");

var issuesService = youtrackConnection.CreateIssuesService();

Task backgroundJobAwaiter = Task.Run(async () =>
{
try
{
await issuesService.ApplyCommand("Project-1090", command: "Comment", comment: "Test");
}
catch (Exception ex)
{
Console.Write(ex);
}
});

backgroundJobAwaiter.Wait();