I had opted for a O2 prepaid M plan last month. The validity was till 20th June 2024. I wanted to change my plan to the € 9.99 one and ordered it online. I did a bank transfer of €9.99 to Telefonica Germany and it was successful. But I received a mail saying:

Thank you for being an o2 customer. Below you will find all information and updates about your tariff.

Your phone number
You can reach them at  ###########.

Your booked packs

Your pack o2 Prepaid Data Pack M costs 9.99 €.
Your credit was not sufficient. If you top up by June 23, 2024, the pack will be activated automatically. *)

Information according to the Transparency Regulation:

*) You can exercise your right of withdrawal within 14 days.
 

The pack costs €9.99 and I transferred exactly that much and it still says that the credit was not sufficient. What does this mean? 

I also tried sending another €0.01 thinking maybe I am supposed to pay € 10. But nothing happened. My plan is not activated. It says "ordered, waiting to be charged".

Kindly help me!

Thank you.

Edit o2_Sven 21.06.2024/12:12: Moved thread from o2 Mobilfunk: Rechnung to English o2 Community: Mobile