Hello @Merreltc and welcome to our English Community 

Have you already registered your o2 Prepaid number at our online portal Mein o2 or installed the o2 App on your phone? 
If so, you can easily release your number into freedom by yourself 

While logged in to Mein o2 simply navigate to “Tarif & Optionen” > “Rufnummernmitnahme” > “Rufnummer jetzt freigeben”
After doing that your new provider can go and get your number from us.

Please let us know wether everything went well or if you’re still in need of assistance 

Take care, Rebecca

Hello, I need to have my prepaid O2 number released to be ported to Vodafone. Did not find the option on Mein O2 app to do it myself.

Hello @7eo4uE2f ,

welcome to the o2 Community .

Do you maybe have multiple contracts? In that case you should register and log in with the number that you want to actually release.

Kind regards, Sven

I do not have multiple contracts. There is no menu/option in my O2 app to release the number. I went to a O2 shop in Berlin and they could not figure out why is it even necessary. They said everything looks alright in my account and prepaid numbers do not need any other procedure for porting. I called the prepaid customer care and they asked for a 4 digit PIN number which I did not find in my account because it is not applicable to prepaid SIMs. 

Hey @7eo4uE2f ,
thanks for your message. 
Follow the Link to read more about transfering your Number:
Call number transfer o2 Prepaid | O₂ Community (o2online.de)

Number transfer to another provider

The number must be released first of all. This can be done on the hotline, in the chat and also via the Mein o2 app. The porting is free of charge.*

1. Download the Mein o2 app and log in or register.
2. Choose: Tarif & Optionen -> Rufnummernmitnahme –> Rufnummer jetzt freigeben. On the next page, you will see the data that must be entered for the new provider**. The approval is confirmed by SMS and is valid for 30 days.

Your Number should now be ready for porting.
Kind regards, Matea