Hello Lynn,
From you account, you have an active product of AVG TuneUp - Unlimited valid until 2018.9.22. I don't see AVG Antivirus product in your account. I have sent you an email, please attach the proof of purchase for AVG Antivirus program to locate the details and assist further.
I've recently purchased the upgrade for my free copy of AVG Antivirus; however, even after following the directions, which came with my Emailed Order Confirmation, there appears no means to activate the upgrade.
Can you help with this, please.
I have received the Email, thank you.
Already had the free version installed. 
Thank you for the screenshot. I have escalated the case to the concern team to fix the issue. Post that you will receive the email confirmation. Meantime, please follow the email steps to install the trial version.
Hello Lynn,
From you account, you have an active product of AVG TuneUp - Unlimited valid until 2018.9.22. I don't see AVG Antivirus product in your account. I have sent you an email, please attach the proof of purchase for AVG Antivirus program to locate the details and assist further.
I have sent an Email response, with the order confirmation number, and an image of the Email I received, which confirmed purchase.
Thank you for confirming this. You will be able to activate the free version once the issue is resolved. We appreciate your time and co-operation.