Lidl surfstick: Internet problem

Hallo!

Sorry but I don´t understand German, hope you can help me.

I bought a Lidl Surfstick 5 days ago and I unlock the SIM in lidl-mobile perfectly. I had Internet connection until today. The problem started yesterday. When I open Mozilla Firefox or Chrome, the page redirects me to o2 freischalten ("http://freischalten.o2.de/lp/sp-prepaid-nicht-registriert?o2_type=goto&o2_label=sp-freischalten") but the page don´t load and I can´t access any page. I have 15€ in the SIM card, so I should connect to Internet. I tried to access to o2 freischalten in my friend´s house and I put the Mobilfunknummer and the Karten-nummer but the page says the data is wrong.

I´m desperate because I need Internet connection.

AW: Lidl surfstick: Internet problem

Yesterday I activated the "Monatsflatrate" with 15€ but now I have -1,98€ in my Fonic "Guthaben"
Can´t I access to internet because I´ve got -1,98€?

AW: Lidl surfstick: Internet problem

Hey (sry if my english isnt so good),
did you found out what happened ? Because i have the same problem with one of my SIMs. it worked fine but since 2 days it stopped working and i have 15 € left. i dont understand why this happened, i already tried to activate it again but also this dont work i have no idea what else i should try ...