Water coming out freezer door. water drain tube is open and running when I turn off frig. But

Question

water drain tube is open and running when I turn off frig. But during normal use it tends to freeze up in the colection area and when it does go into its defrost cycle the water trickes down and puddles in bottom of freezer and then makes its way out of the door on to the floor. Is tyhe defrost thermostat not working correctly or is the defrost timer not shutting down long enough? Tim