Is Dirk Gently gone from Netflix?! It's one of the best things there.
I thought I still saw it listed recently. Maybe it's only gone from your region and not mine, in which case I recommend a VPN.
It's still there, but because the BBC didn't get a lot of traction with it in the UK they canceled further seasons.
I frankly was surprised to even see a season 2. Season 1 was brilliant, but it didn't seem possible to do a follow up that wouldn't be lame. I was wrong, but I'm still happy we got these two seasons. I imagine it's pretty hard to keep up this level of weirdness.