Sounds like you've ground it a little too fine and maybe you're sucking too hard on the inhale.
I've used an Airizer Solo II for years and it's my preferred tool at this point. Once it comes up to temp, I "sip on it like a cup of tea". I'm inhaling just hard enough to pull air from over the herb as it's toasting, in a long, slow drag, not a hard hit like on a joint or a bong.
Hopefully it's just your technique keeping ya from enjoying the dry herb vape life, as since converting from combustion, I've saved tons of money on grass since its so efficient.