Uninstalling AVG on my Mac in order to install newer version

When I double click on the AVG AntiVirus app in my Applications folder on my Mac desktop (in order to follow the instructions for installing the newer version), the older app does not open. I am instructed to uninstall the older version so I can install the newer one.  The older version is apparently installed but not working.  Please help.

Thank you. 

Hello Leslie,
Thank you for reaching AVG Support Community.
We're glad to look into this and help you.
Please refer the below article and select your device as "Mac" and follow the steps to uninstall and reinstall the latest version.

Uninstalling AVG Internet Security

Installing AVG Internet Security

In case, if you face any technical difficulties or need more assistance, please let us know, so that we will help you with additional support.
Thank you.

Hello Leslie,
Thank you for reaching AVG Support Community.
We're glad to look into this and help you.
Please refer the below article and select your device as "Mac" and follow the steps to uninstall and reinstall the latest version.

Uninstalling AVG Internet Security

Installing AVG Internet Security

In case, if you face any technical difficulties or need more assistance, please let us know, so that we will help you with additional support.
Thank you.