I had exactly the same issue with my Hayward SWG. Flow switch was stuck closed kept generating and it wasn't on a timer. I would get low salt errors and my salt readings were incorrect and it would cause the swg to stop generating chlorine.
For the flow light to be green, the flow switch would have to be stuck in the "closed" position... But the real problem is that the salt system should not be getting any power when the pump is not running.
In the old days of single speed pumps, you just powered the pump and the cell from the same timer... Easy Peazy... With VS pumps you can't do this because the pump gets constant AC power and has its own timer/control panel...
What most people do is to run a separate timer for the SWCG that is set to provide power to the cell only when the pump is scheduled to run.. So, since your unit has been running fine, why would you go to all that trouble??? Because it is possible for the cell to explode, if allowed to generate chlorine gas while the pump is off. It is rare, but does happen..
The cell was designed to be controlled by a Pentair automation system, which is wired to prevent the cell from getting power when the pump is off..
The same would apply to your acid injections system, although it won't cause an explosion..