Game is lagging After Building

Hello,
I am working on a level. I have created LODs and setup the culling, and I am getting 60 FPS in the editor but when I build the game I was getting 20-30 fps, when I monitored my computer resource utilization I saw that, When I launched the game in Unreal editor my GPU was utilized around 30-355, but in build, it was using around 10-15%. Also at a certain area in the level, the resource being used less than in other areas
I am using a laptop with IGPU and with an EGPU
IGPU is From AMD
EGPU is RTX 3050
The engine Version is 5.2.1

Thank You