iPod IP address does not match my wifi IP address?

We have this pre-paid wi-fi internet called Stelera, it puts wi-fi all through our apartment and you can plug it in to a PC and it gives it internet as well.

Anyways my ipod use to work with the wi-fi but one day I was at this place that had wi-fi so I tried connecting to it, it did not work so I came back home and now my wi-fi is not working on my ipod but the w-fi is working on everything else, I found out that it's because the IP address on my ipods wifi no longer matching my stelera wi-fi IP address, is there a way I can change my ipods IP address to match my stelera IP address?