MN-500 Internet can't stay conneted

This happened oneday without knowing anything
In every 5mins range, my Broadband connection gets disconnected. I tried
everything to fix this. I tried renewing IPconfig, reinstall the ethernet
adapter,but nothin worked.
In my Network Connection, Gateway icon disappears for no reason and comes
bak after resetting the broadband. Not only that, my ethernet adapter shows
that information(internet) is being sent but is not receiving.
Base Station MN-500