After Norton updated I got a warning that my Trial Period Has Expired

Yesterday I updated Norton and after that it showed a red X over he Norton symbol then a warning popped up that my Norton Trial Period Has Expired .I found a posting on here how to fix it and it worked OK yesterday. Today I started the computer up and I got the same warning again  that  my trial subscription had ended.I have had a paid for subscription for many years so I do not know what is going on . Need help fixing this .