How do I cancel automatic pre-paid renewal?

I have an O2 My Pre-Paid M that is automatically pro-longed every month as long as I have enough credit on my account. However, last month I also needed extra data and bought a Pre-Paid Data Pack L, through the Mein O2 App. Now when I added credit, it automatically renewed the Data Pack, which I don't want or need.

Have been trying to click around in the app but can't seem to understand, where I can cancel the automatic renewal?

Hoping for answers here as visiting an O2 Shop always means a huge line and taking forever before you get any help....