Is it getting hot? I would increase the temp, since you can't really depend on low priced digital units to be accurate. If you crank up the heat and get vapor, just find your temp range. See what setting you need on the low end, to start getting vapor, then find the high end, where your vapor is harsh and the remains are a really dark brown. Somewhere in the middle is where you want to be. Also, turn the fan down. The more air you're pulling into the unit, the more you lower the temp. Even with passive whip vapes (no fan), you can pull hard enough on the whip so that you'll lower the temp down below vapor range.
If increasing your temp (all the way if you have to) doesn't get you any vapor, then you've got a defective unit. Get it fixed/replaced before that 90 day warranty expires.