I am doing a project on a parking garage. It will hold 25 cars ,then a light will illuminate that says lot is full. Then when one car leaves lot light will go off. I have everything set up for light to come on, but when I get one car to leave the light will go off, but will come back on. My instructor told me that I needed to do a compare on count up and count down. I tried this but it is not working. I am sending an attachment for the diagram that I have used for project. This is for Allen-Bradley PLC. Any help would be greatly appreciated, as I new to all of this. Thanks!