Help with billing around upgrade from Office 365 Personal to Home

Greetings!

Can anyone please try and explain what has happened as a result of my recent upgrade from Office 365 Personal to Home?

I had a $99 Personal subscription advance paid until November 2020. As a member of my family wanted to use the package, yesterday I followed a link that said UPGRADE and upgraded to the $129 Home version. The full $129 has been taken from my bank account to pay for the so-called 'upgrade' and I was waiting to be refunded for the balance of the old $99 subscription. When I contacted support today they informed me that I was not due for any refund. In fact, the whole conversation got so completely surreal I thought I was in some insane twilight zone.

It seems that I am now paying twice for two separate subscriptions between the months of April 2020 and November 2020. That means I was not UPGRADED by Microsoft at all, I was just hoodwinked into purchasing an entirely new and separate subscription on top of the one I already had.

Am I missing something here?

Thanks to anyone who can enlighten me around this.