@Looneybin1978 Try temporarily disabling AVG, as described here:
https://support.avg.com/SupportArticleView?l=en&urlname=Disable-AVG-Antivirus
As long as you don't do anything other than try to play, your computer should be safe. If this helps, you can set exceptions for Origin, Steam, and Sims 4 (TS4_64.exe) within AVG.
Otherwise, please contact EA customer support to make sure that there's nothing wrong with your Origin account or the link to your Steam account, or your copy of Sims 4 for that matter.
https://help.ea.com/en/contact-us/