Hey @Choy ,
welcome to the o2 community 
Your quaestion can be simply explained.
You booked o2 My Prepaid M.
This is the reason that 7,49 EUR were debited.
Kind regards, Matea

Hello O2 team, I have booked a prepaid package on existing number which is newly received. I want to make sure the package I applied for it will be activate on my number and how much time it will take. Thanks! 

Have you ordered a prepaid card with your phone number ported at the same time?

@Bumer I ordered first Free Sim and activated and today I ordered a package on SIM but it seems they are going to send another SIM. Could you make that package should be activate on Fre Sim? 

are you registered for My o2 with your phone number? You can book the right pack there.

Yes I am registered but what about that one? It is in German and very confusing and I ordered one which was wrong. Could you resolve first my issue? Make sure first that will cancel first then I will do new one. I don't know how to do cancel. 

revoke the new card to: widerruf@cc.o2online.de 

Hello @akh_nav 

Welcome to the community.
You have already received the right answer from Bumer.
Please cancel the new SIM card using the email address provided.
Then log in to the portal/app with your active phone number and book the desired pack for this phone number. 

Best regards,
Maria