Newton assumed one universal time, ticking the same everywhere — a single clock the whole cosmos runs by. For two centuries it seemed obvious. It's also wrong.
Einstein showed that simultaneity is relative: two events that happen "at the same time" for me can happen at different times for you, if we're moving differently. Worse for the master clock — time itself runs slower the faster you travel, and slower again the deeper you sit in gravity. This isn't a thought experiment: the GPS in your phone only works because engineers correct for the satellites' clocks ticking faster than clocks on the ground.
There is no clock the universe checks against. Every clock keeps its own honest time.