LTE data volume "Unlimited Max" Sim Karte Problem!!!

Dear All,

I have a short question:

I have ordered PostPaid SIM card “O2 Free Unlimited Max Flex”, it arrived, but it is not working with my LTE Router, no any signal… Any ideas why? I can not contact any O2 service, because I do not have an O2 mobile number (everywhere they ask for it first)… I am very confused, I have Kunder-Nr, I paid ~55 euro for the Tarif and 40 euro for the Anschlusskosten, but there is neither internet, nor contact/help service… Is this how O2 works in Germany??? :(