I chose to buy IS.
Unfortunately, when I entered my e-mail address for the purchase, I entered the wrong info, so the code has accidentally gone to a “catch all” address that should be forwarded to me (but hasn’t been).
I then created an Avast account with the correct address but this says that I only have the free version of Antivirus.
As payment has been made for Internet Security via my PayPal account, I’d like to know how I can get what I’ve paid for?
Try the following: https://support.avast.com/support/tickets/new.
Support tickets are handled on a First In First Out and can take between 1 and 5 working days, whatever you do don’t submit multiple tickets as this throws you back in the line.
Whilst you won’t be able to give an order ID, etc. as you won’t have received an email. Give as much information as possible, date of purchase; product purchased; payment method; your name and address; your email address. If the typo is a simple transposition or incorrect domain name of your email they should be able to find something close.
Thank you very much I will do that. 
You’re welcome.
Give it a little time, if you haven’t heard anything after 5 days, get back to the topic and post the support ticket ID number and we will try to push it for you.