Getting the internet access via wifi hotspot

Hello, guys! Need help, no HAAAAALP with the wifi hotspot on my iphone 4s. everything's cool and I'm connected to the 'iphone' wifi network but without internet connection! tried different network settings on mac like setting DHCP on or static ip. no results. the worst part of the story is that one week ago I successfully used it but now it is not working and this really makes me throw the **** macbook in the wall