I've written a Wandsmith sublcass for Artificer and am now trying to import it into D&D Beyond. I have everything implemented but I am having a heck of a time getting the following core feature to work as intended:

Spellcharged Wand

3rd-level Wandsmith feature

You have learned how to imbue wands with magic to create a powerful item. When you take this Artificer specialization you can create three types of spellcharged wands each imbued with a different type of magic as shown Spellcharged Wand table.

Wand	Magic	Spell List
Arcane Wand	Arcane	Wizard
Scepter of the Divine	Divine	Cleric
Thorned Branch	Primal	Druid

For each Spellcharged Wand, choose one cantrip, one 1st-level spell, and one 2nd-level spell from the spell list for that wand. The spells must require 1 action to cast, and casting that spell must not require material components that have a gold cost, or are consumed by the spell (as indicated in a spell's description). You can choose additional spells in the same way when you reach certain levels in this class as shown in the table below. When you choose a new spell, you can replace any of the spells imbued into your spellcharged wands with another spell of the same level from the wand’s spell list. 

Artificer Level	Spells Gained
6th	One 3rd-level spell
9th	One Cantrip, One 4th-level spell
14th	One 5th-level spell

When you finish a long rest, using woodcarver’s tools you can magically turn a spellcasting focus wand that you are holding into one of your spellcharged wands. Your spellcharged wand can be used as a spellcasting focus for your artificer spells. The wand continues to be a spellcharged wand until you use this feature again or you die. You can have only one spellcharged wand at a time.

When you create a spellcharged wand, it becomes imbued with the spells chosen for it. While holding one of your spellcharged wands, the spells are considered learned, and they count as artificer spells for you, but they don't count against the number of artificer spells you prepare. You can also cast each of the wand's imbued spells without expending a spell slot. Once you cast any of those spells in this way, you can’t cast that spell in this way again until you finish a long rest.

 
Specifically, I am having trouble getting the 6th, 9th, and 14th level options to work. I would like it to function in a way that when a player reaches the requisite level, they get new options in the main "Spellcharged Wand" feature, similar to Artificer Infusions. I have gotten options set up for the player to choose a Spellcharged Wand, then a Cantrip, Lvl-1 and Lvl-2 spell when they reach level 3, but I don't know how to allow to choose a new spell in the same feature when they reach higher levels. I tried fudging it and creating features at 6th, 9th, and 14th level, but got a message that I do not have the correct features at the correct levels. Is there any way to do this?

I would create three Options, one for each of the three wands. Then I would attach Spells to those options for the cantrips & spells and simply trigger them to appear at certain levels. The player will be able to choose all their spells right away if they really want to, but the system won’t actually give them those spells until the appropriate levels.