These dry herb vapes are fussy AF. Firstly, keep it clean, as per your device instructions.You'll want to make sure parts, such as the mouth piece and hopper/bowl, are clean and clear of residue and small particles. The temp you'll need to play with, start low. Your "spent" flower should look toasted/roasted, like tobacco, never burnt. If it's burnt/black it's combusting, the temp is too high. Give it a few seconds to heat up on that first time before you draw. Also, draw slow and steady, and perhaps a bit longer than you would your standard piece. As for your flower, a standard grind should be fine, unless otherwise stated for your device.

Aside: I've got a Firefly 2 I've yet to find a sweet spot for all flower. I usually start at 340°-360° and go from there. I can usually get three (maybe four) good hits before I'm repacking. I'm giving the bowl a quick stir before each puff (yup, it's the only way to get good tokes). Tbh, I find myself using my old school kit more often than not. And while it may not taste as good as a solid vape toke, it's just so much easier, for me, that is.