routing issues

probably is a routing issue and I’m strangling myself to solve it without any luck. i have installed one routerboard 433 as AP and another one as repeater. the AP is connected to an internet router for access to the outside world. I’m trying to ping the gateway of the internet router without any success. i’m pinging successfully the interface of the AP which is connected to the internet router but not the gateway to access the internet.
the default route 0.0.0.0/0 is pointing to the outside interface (the one which is connected to the internet router)

Any help will be appreciated

anyone??