LiveUpdate and Virus and Spyware Scan and Definitions not working

Hello,

I have Norton 360 Premier Edition, with 18 days remaining on subscription. My Norton PC Security screen tells me that my Virus and Spyware Scan, and Definitions Update, is not up-to-date. But when I run a manual LiveUpdate, it says it's successful, but the last update date shown is from December. It also won't complete a system scan, it keeps saying that it is working, but it never completes the scan. 

I have used the Norton product for many years, re-subscribing each year.

Any advice would be welcome, thank you!