Art it looks like your fire was not hot enough and when making wood fired pizzas you need to go easy on the toppings because they cook a pizza in 2 to 4 minutes.
Now I have only used my Uuni 2 a couple times myself. Once for two pizzas and another to sear a couple of pork chops so I am still learning.
The initial fire is important as is the height of the pellet feed tube. The higher the tube the hotter the fire. The more pellets your start with the hotter the initial fire will be then the tube will feed pellets and maintain the fire size depending on how high the tube is.
Here is a picture of how high my tube is...
Now here is how I light my fire on the Uuni 2
1. I fill the pellet tray up with 2 handle scoops of pellets
2. I slide in the pellet tray 3/4 in leaving partially exposed to hit it with my MAPP gas torch
3. After hitting it for about 30 seconds I get it to sustain a flame. Then slide it into place.
4. Leave it be for a few minutes with the pellet hopper lid removed. Put the front panel in place.
5. When you place the pellet hopper lid in place this will start the drafting from the chimney and pull the flame across the pellets. Give it a few more minutes.
6. Now that you have a strong fire you can slowly add pellets to the hopper tube. Try not to dump them too quickly and put out the fire. Once loaded with pellets place the hopper lid back on. Give it a few more minutes to get good and hot.
The original Uuni was a little bit faster to start because the fan creates a draft and with the new Uuni 2 you have to wait for the natural drafting to begin. This requires that the chimney is hot. As the hot air rises it actually pulls more air with it creating a draft. I used to get my Uuni ready to cook in about 12 minutes. The Uuni 2 seems to be more in the 16 minute range. But it does not use as much pellets as the first Uuni.
And when cooking a pizza in it you gotta be quick. When it is up to full temp. I find that the 1st minute sets the pizza then I do a quarter turn every thirty seconds. My pizzas are done in no more than 4 minutes. But they are also thinner crust and light on the toppings.
It will take a little practice but once you get it down you will be cranking out quality pies
Tim has my number so you have my permission to get it from him and give me a call if you want me to walk you through it or if you have more questions.