Preheat the oven to 350°F (175°C). Grease a 9×5-inch loaf pan or line it with parchment paper.
In a large bowl, whisk together the almond flour, coconut flour, erythritol, baking powder, baking soda, salt, pumpkin pie spice, and ground cinnamon until well combined.
In a separate medium bowl, beat the eggs. Add the pumpkin puree, melted butter, and vanilla extract, and mix until smooth.
Pour the wet ingredients into the dry ingredients and stir until just combined. Do not overmix.
Pour the batter into the prepared loaf pan and smooth the top with a spatula.
Bake for 45 to 50 minutes, or until a toothpick inserted into the center comes out clean.
Remove from the oven and let the pumpkin bread cool in the pan for 15 minutes.
Transfer the bread to a wire rack to cool completely before slicing.