Shady business - Final demand for payment !

I sometimes use Teamviewer for my business and as such I took out a licence with them. I took out a licence on their website and when I wanted to pay it via EFT from my credit card I battled a bit so I re-entered their system from the link from the TeamViewer program and simply paid by entering my credit card details and gave it no further thought. I was given an activation code that I entered and my program lists that I have a business licence that is active so I gave it no further thought. (This was in August of 2019).

3 months later I get a final demand from their collection agency. I was totally shocked as I have only 1 licence and this is paid for. I use only 1 laptop and have only logged in from this 1 laptop and now suddenly they are demanding a second payment. I was stumped. Surely if they had not received my payment they would have blocked my access. So I rep**** to the collection agency stating that I have 1 laptop and it's licence has been paid for. They told me that 2 invoices were issued to me. Their attitude is simply that I agreed to their terms and conditions and had enough time to cancel and I didn't. I didn't even realize that a second invoice had been issued! Never minding the fact that the '2nd licence' was never even used.

Now I'm expected to pay for something that I never used ! and that when I was trying to 'do the right thing'.

I have no idea how to resolve this and simply cannot justify spending this kind of money for something that I don't need (the second licence) and do not use.

I am not a lawyer so I don't even know if I have a foot to stand on !

It is because of companies like TeamViewer that people pirate programs. I will not be renewing my subscription and I will be advising all my clients to no longer make use of their services.