Confusing renewal messages from Norton

I have started getting alarming messages from Norton stating variously that my Norton 360 is about to expire, is imminent, or has already expired and my computer is in danger.  The program itself says there are 22 days remaining, but refers to a 'trial' whereas it is a 12 month subscription. My computer records say installation was April 17, about three months away.  

All very confusing.

How should I respond to this? I don't want to pay up prematurely, on the other hand I don't want to risk not being protected. Where can I get a quote for the cost of renewal, including the option of upgrading the product? I understand that 360 is now somewhat dated and not really designed for Windows 10 which I now have, and that I should consider Norton Security Standard, for one device.

Some advice would be appreciated.

Windows 10, 2-in-1 tablet upgraded from Windows 8.1. United Kingdom.