(DND 5e) Item Pile Module not showing price for items

I am trying to use the item pile module by wasp to make merchant actors, but whenever i add items to the merchant it shows as free, and it won't let me change the price. Does anyone know what might be the problem? Here's a few screenshots of the steps i'm doing:

1. Created the actor as an npc

https://preview.redd.it/zdvomdrqv0dh1.png?width=815&format=png&auto=webp&s=99c6e4e3e997d0064fb480d877a645addc509a30

2. Clicked configure

https://preview.redd.it/vg3pabotv0dh1.png?width=828&format=png&auto=webp&s=ff1bde70e2197c7b8bc165b7b04574386ba67348

3. Enabled as a merchant item pile

https://preview.redd.it/9cgi4r01w0dh1.png?width=699&format=png&auto=webp&s=933b303e2efd9b7b0e5e803c91bdc0b37f462e55

4. Added a standard greataxe to the shop

https://preview.redd.it/mmui5uycw0dh1.png?width=809&format=png&auto=webp&s=5ad09d5d7d200e43899cd43bcb025fefce1cc26f