navigation not working
 

Can anyone help me figure out why my navigation on http://www.consulenza-finanziaria.it/ is not working?? I'm using a theme called Powered Business WordPress Theme. I have got many posts which 6 are showing on the index.php but when i click on page 2 it shows the same posts |huh

I have tried so much and literally can't find any solution to it |banghead|

If anyone has any ideas on how i can solve this issue please let me know, thank you.