[Freeswitch-dev] sofia profile stop response

hey all, I have experienced a lot of times that sofia profile stops to response for any sip messages. And when you type sofia status, that profile is gone, but if we check the port by netstat, the port is still opened by freeswitch. This happens if we keep freeswitch running in 1 - 2 days. And there is no error log. Any idea on how to debug? Cheers.