The WWE Night of Champions 2020 event (which was actually held under the name "Clash of Champions 2020") had a running time of about 3 hours. This event took place on September 27, 2020, at the Amway Center in Orlando, Florida.
For clarity, the "Night of Champions" branding was replaced by "Clash of Champions" in 2020, so the event you're asking about corresponds to Clash of Champions 2020, which lasted roughly 3 hours.
