Unable to top up guthaben

I had the prepaid sim whilst in Germany for a year and when I got back to England I let the credit go to 0 as I wouldn’t be using it anymore. I am returning to Germany for a few days and want to use the SIM card again as it will be cheaper for me. I have chosen my tariff but I still can’t get any money into my Guthaben. I still have a german bank account that the money came from before but I can’t top up my Guthaben

Can someone help please?
Edit o2_Bianca 27.10.23 12:58Uhr: Verschoben von o2 Prepaid to English o2 Community mobile