[Nikky]

You can do it:
1 - go thru WAN settings and reselect / retype selection or data (look posts 8., 11.) + Applay + Save and Reboot and try again
2 - go and bay normal router:
a) leave Kasda in Bridge mode + new router with WAN on input
b) throw away Kasda and bay new router with ADSL Annex B modem on input
Suggestions:
a) http://www.hgspot.hr/opis.aspx?ID=011424 or http://www.hgspot.hr/opis.aspx?ID=020286
b) http://www.hgspot.hr/opis.aspx?ID=020669