regarding existing phone number to new contract

Would you like to bring your existing phone number with you to o2?

yes

Register your transition phone number for My o2. Under Manage contract > Bring phone number to o2 you can order the phone number to be taken with you.

i could not find any option

Tarif & SIM-Karte > Vertrag verwalten > Rufnummer zu o2 mitnehmen.

Hello ​@suhas a,

welcome to our o2 Community 😀

It is usually easy to transfer a phone number online. The prerequisite is that you have registered with your new (temporary) phone number on Mein o2.

Please find all further information here:

Rufnummernmitnahme: Wechseln zu o2 & Nummer behalten

However, if you do not know the name and date of birth of the old prepaid card holder, you should first have the owner change carried out there.

Please let us know if you have further questions.

Best regards

Giulia