How can I check if a cancellation token is existing before I cancel it?

I have this code: public void OnDisappearing() { runPointsChecker = false; timerSeconds = 0; cts.Cancel(); //cts.Token.ThrowIfCancellationRequested(); if (Settings.Mode == Enums.MO.Quiz && App.showCard.Running()) StopQuiz(); //Code to Stop the stop watch and insert the values in the database. ScreenTimeStopWatch.StopScreenTimeStopwatchAndToDatabase(); ScreenTimeStopWatch.KillScreenTimeStopwatch(); } The code block is failing with a null object exception. Can someone give me some suggestions…

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Ubuntu 18.04 LTS UEFI system won’t boot since I applied the latest Ubuntu updates last Sunday 12/29/19

I have an Ubuntu system built 2 months ago that won’t boot since I applied the latest Ubuntu updates last Sunday 12/29/19 and immediately afterwards rebooted the system, which then failed to boot. Up until this latest update this system has been receiving updates and booting with no problems. CPU: AMD Ryzen 7 MOBO: AMD…

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