I bought a Bahn 25 card. I used the card once. Why now am I expected to pay again?

But if I was unaware of the automatic renewal as I am not a German speaker? Can I still send an email to have it cancelled even after DB sending letters threatening court action and fines?

First:
You should stop further automatic renewal, otherwise you will have the same trouble next year again.
You can use the email-contact (https://www.bahn.de/p/view/bahncard/bahncard-services/bah... - choose "Kündigung/Kontakt">"zum Formular")

For the prolongation in the past you will have to pay the Bahncard.
If already fines or fees have been added, they are sometime too high (inflated). In this case you should ask a consumer advice centre for assistance.