There are just few steps for you to edit an item's modifier of your items or options
Login to your Yamimeal Merchent Portal via https://merchant.yamimeal.com/web/merch/#/login
Click on "Menu" -> "Item"
Click on the item's name into the "Item Detail"
1. Click on "X" to delete your item modifier
2. Add your item modifier by clicking "add" on modifier
Submit to add modifier.
Click "Submit" to save and publish your updated modifier
View video below for demonstrations of the procedures above.