First try going into Origin right click on simcity and left click game properties. Disable Origin in game and see if that works.
If not
uninstall origin through start - programs - Origin - Uninstall Origin
Then manually delete the origin folders from:
C:\Users\[name]\Appdata\Local
C:\Users\[name]\Local\Roaming
c:\ProgramData\
c:\Program Files\
Then re-download and reinstalling origin reinstall the game through there
You may need to enable the option to view hidden files and folders to view the Appdata folder. To to this in My computer go to view - options. The tab view and enable Show hidden files, folders and drives.