You have a problem where AVG antivirus is prompting you to upgrade all the time.
What has probably happened here is that you have installed the wrong version. You wanted free and you installed the trial version.
AVG does try to ‘direct’ you towards the full product as a trial version. The free version is generally cleverly made less accessible on their website. Remember though, this is a free product and offers the same scanning and detection capabilities as the full version so they are doing you a favour by giving it away. You can’t blame them for wanting to make some money!