Deproject Screen To World Node doesn't work on Begin Play?

I’m trying to use deproject screen to world to clamp the camera when jumping relative to a mobile screen. I used deproject screen to world to get the WorldLocation_Z of Screen_Y and hooked it up on BeginPlay but it doesnt give me the right Coordinate.This is just on BeginPlay. On Tick it works but I need it as a initialize variable. I dont want the camera attached on a player, I interpolate it to the player. Is there another way one woud adjust world locations relative to mobile screens? Is it a wrong approach?