Double charge on first invoice

Hello! I just got my first invoice and I notice that the Anschlusspreis Option O2 HomeSpot is been charge double for the same amount. Can you guide me on why this is happening and how i can get it fix. Also, i was told that i can get my first invoice cost reduce since it took 2 weeks for the sim card to arrive so i was without access to internet for that time, 

thanks

karen