Freeradius doesn't record acct-stop-time.

Hi... My freeradius are recording in mysql all sessions about start connection, but it didn´t finish it. when a device is logged out it remain connected at mysql, doing my proprietary CRM mistake to return connection data. Checking detailed log, its registering start connection and stop connection, the problem is just in mysql... It is probably a configuration that I should enable, but I don´t know wich. Can anyone help me.?