it says my pickaxe is too expensive to enchant when it shouldn't be

I enchanted my netherite pickaxe with fortune 1 at an enchanting table, then I used the enchant command to put mending on it, and finally I enchanted efficiency 4 on it with enchanting books and an anvil. I got a unbreaking 1 book and tried putting it on the pickaxe at an anvil, and it says too expensive.