Infini solar 3kw help required

Dear all require help I have infini 3kw (not plus) I purchased second hand. I have set it up on off grid without battery. The problem is that it only switch on when pv is available. During day time it shares electricity from wapda as well. When sun goes off it switches off even grid is available.

Setting priority PV–>Grid–>Battery

Then I checked with batteries it works fine untill battery is up. When battery disconnect itself when it is fully discharged inverter goes off and don’t turn itself on when wapda or grid is back. I have installed change over and daily change over to solar and to wapda. Is it it’s normal behavior of inverter or it has Some fault? Please help