November 2020
I tried to update Sims 4 & i accidently cancelled it & when i try to start Sims 4 i get a message telling me that i should uninstall the game.
If i do so all saved things in the game will disappear forever huh?
December 2020
@Supermatthea Your saves and other user content are stored in the Sims 4 folder in Documents\Electronic Arts. You can back up this entire folder if you want, then put it back after an uninstall. You may not have to though—the uninstall process doesn't always delete this folder in the first place.
As for the game issue itself, try repairing: open your Origin game library, right-click on the Sims 4 icon, and select Repair. Then you can try updating again.