During the (rare) times issues such as these have been reported, the primary recommendations which have resolved issues such as these are:
1 - Make sure the interior of your oven is completely dry - water is a pizza ovens worst enemy. If your ovens exterior is damp or wet for any reason, it's a sure bet that your cooking floor of your oven are also damp as well, (These interior stones can absorb a lot of water without it being visible to the naked eye and the cooking floor will not heat up to the desired temperature if there is any dampness at all inside your oven (It is for this reason that the manufacturers recommend that all ovens be covered during times they are not in use).
If this is the case, resolving the issue is simple: either repeat the same curing process with your oven that you did when you first received it, or alternately, keep a small fire burning within it for several hours (without cooking in it). This will remove any residual damp from the inside of your oven and from then on the issue should be resolved as long as your oven remains covered when not in use.
2 - Another common reason for issues such as these are that you are not making the initial fire wide enough. The wood should first be placed in the in the front to middle of the oven and then once lit and burning well, the wood should be spread 12"- 14" on the cooking floor to make sure the entire floor surface is getting hot. Once it’s very very hot, move the fire to the side so you can cook on the hot floor. Throughout the cooking process, the heat on the floor may cool after multiple pizzas or other dishes. In those cases, you can simply move the fire back to the cooking space in the middle to reheat the floor. Make sure you wait long enough for the floor to heat before moving the ash and wood to the side. When you have the fire directly on the floor of the oven, it can’t help but reach optimal temperature.
3 - Make sure the wood you are using is not wet, soft or not seasoned (all of which can cause issues with the floor heating).
We've also including some links to articles we’ve written in regards to cooking in these ovens which may also help:
https://www.patioandpizza.com/blogs/resources/cooking-in-your-maximus-wood-fired-pizza-oven
https://www.patioandpizza.com/blogs/resources/how-to-cook-margherita-pizza-in-outdoor-pizza-oven
https://www.patioandpizza.com/blogs/resources/wood-for-pizza-oven
