do you have a prepaid card?

yes

how would you like to charge?

I already did so via paypal but still balance is negative

how long ago was that?

I tried it few days ago and today again! 

What does tried mean? Did the money go from PayPal?

yes It did, but the Sim-Card balance is still negative, with this message: Mein Guthaben

-1,53 €

Gültig bis: 12.04.2025

ask in the chat.

o2 Prepaid-Chat

I tried the O2 Prepaid Chat several times but this error comes up : Es ist ein technischer Fehler aufgetreten. Bitte starte den Chat neu. 

Log out here, then log in with your mobile phone number and then click the link.

Hello @quantumlife1311 ,
welcome to our o2 Community. 
I have just checked. 
The last top-up was on 11.10.2024 for 15,- EUR. 
This amount was offset directly against the fees already due for the o2 Prepaid Data L Pack.
Nothing more was received after that. 
Please call the  Prepaid-Hotline : 0176 88 85 52 82  (Mon-Fri 7:00 to 20:00, Sat 10:00 - 18: 00) 
Kind regards,
Solveig 

Many thanks for response! I can not call as I cannot do the aufladen! 

Hello @quantumlife1311 ,
please call from another phone or top up a small amount to be able to make a call. 

Kind regard, 
Solveig