Idling drops suddenly!

The LPG inline system is installed on my vehicle. After the vehicle starts, there is no problem switching from gas to gas. But then the idling drops even when the car is moving, even below 10 and the engine shakes itself.

Maybe he does this problem once a month, but he does it all day long. What do you think is the problem? I wanted to point out that there is a constant smell of gas in my vehicle and it may be related to the issue.

What do you think is the problem of my vehicle? What needs to be repaired and changed for solution.