Error while access mainframe terminal

System.InvalidOperationException: The activity ‘Send Control Key’ with ID 6238 threw or propagated an exception while being canceled. —>
System.Exception: Terminal error: Timeout\r\n at UiPath.Terminal.Activities.TerminalActivity`1.EndExecute(AsyncCodeActivityContext context, IAsyncResult result)\r\n at System.Activities.AsyncCodeActivity.System.Activities.IAsyncCodeActivity.FinishExecution(AsyncCodeActivityContext context, IAsyncResult result)\r\n at System.Activities.AsyncCodeActivity.CompleteAsyncCodeActivityData.CompleteAsyncCodeActivityWorkItem.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)\r\n — End of inner exception stack trace

Can anyone help me on this error?