Engraving (Fill) but seem like only outline

[Cmsigns (Jason nguyen)]

Hello everyone. I’m very new to laser engraving. I have a 80W chinese red/black laser. Trying to do some solar sticker for customer.
By some how, i’m setting the machine to run on
Speed 600/ pwr 19% the engrave turn out fine except for small text got double line instead of fill.
Design using illustrator, lighthburn version 1.0.04

The preview show it’s a solid fill text.

Tried slower the speed but does’t make any change.
Does anyone know what could be the problem?

Thanks in advance

[Cmsigns (Jason nguyen)]

Here is my setting

[Cmsigns (Jason nguyen)]

Hi michael.

1. Yea i do have air assist as i can feel the air blow out where the nozzle is
2. Is there anything wrong with this setting? As im new to engraving so i just done the test to find the good setting on material
   
   
   
   Here is the test i’ve done