There are two cases when automatic door cannot open and close properly. One is closing the door a little while re-open at once; the other is keeping open or closed.
One is closing the door a little while re-open at once.
The reason is that the presence of interference in range of the sensor
sensing, such as: direct sunlight, an object of activity, unstable light source.
You can cut off the sensor signal lines to test whether the interference caused
by the signal sensor, which automatic door can not be closed.
The other is keeping open or closed
The reason is that the sensor is damaged and there is always a door open signal is input to the automatic door controller. It may be automatic door openers or the mode switch is adjusted to the open state, if it is installed access control systems, may be access control systems relay damage.