PETG infill top issues

[hollow tulip]

I've been printing with orca lately @ around

350-600mm/s & 10k accel.
Delta 4028 running @ 40-100% depending on layer time.
Bridging speed @ 75mm/s
CHT Hardened steel nozzle 0.4mm
0.5 linewidth
0.25mm layer height
Thick infill bridges ON (default)

Idk why the first layer on my infill is never flat, it rises lik in the picture and makes for a terrible top surface

i already turned off thick bridges for & noticed my normal bridges are better.

should i turn off thick internal bridges as well ?
lower briodge flow ?

i dont think this is true at all, its usually worse for me than good