My jacuzzi keeps emptying into the pool when the pump switches off and then refills from the pool when the pump comes on - do you know what the problem is?

I use to be able put in service mode and fill spa, does not work.I have turned valve in a few different postion & does not fill spa.

Had a new Circut Board put in a few months back from a lightining strike, Have not try to ise until a few weeks ago I use to be able put in service mode and fill spa, does not work.I have turned valve in a few different postion & does not fill spa.
Had a new Circut Board put in a few months back from a lightining strike, Have not try to ise until a few weeks ago

First thing I would look at is the CHECK valve...This valve will stop the flow of water from seeping back into the pool from the spa when the pump is off. Every spa should have one.The valve should be located at the pump... BEFORE the water enters the pump itself on the spa side. If there is not a check valve add one.(problem solved) If there is a check valve it will have a window on it and you will be able to see the flow. 
If thats the case the Jandy system itself may be pumping the water out of your spa at night during freeze protect mode. First thing I would look at is the CHECK valve...This valve will stop the flow of water from seeping back into the pool from the spa when the pump is off. Every spa should have one.The valve should be located at the pump... BEFORE the water enters the pump itself on the spa side. If there is not a check valve add one.(problem solved) If there is a check valve it will have a window on it and you will be able to see the flow.  If thats the case the Jandy system itself may be pumping the water out of your spa at night during freeze protect mode.