[Bug]: Admin - Can't create promotion 'off order'

[dan-long-dev]

Package.json file

{
  "name": "medusa-starter-default",
  "version": "0.0.1",
  "description": "A starter for Medusa projects.",
  "author": "Medusa (https://medusajs.com)",
  "license": "MIT",
  "keywords": [
    "sqlite",
    "postgres",
    "typescript",
    "ecommerce",
    "headless",
    "medusa"
  ],
  "scripts": {
    "build": "medusa build",
    "seed": "medusa exec ./src/scripts/seed.ts",
    "start": "medusa start",
    "dev": "medusa develop",
    "test:integration:http": "TEST_TYPE=integration:http NODE_OPTIONS=--experimental-vm-modules jest --silent=false --runInBand --forceExit",
    "test:integration:modules": "TEST_TYPE=integration:modules NODE_OPTIONS=--experimental-vm-modules jest --silent=false --runInBand --forceExit",
    "test:unit": "TEST_TYPE=unit NODE_OPTIONS=--experimental-vm-modules jest --silent --runInBand --forceExit"
  },
  "dependencies": {
    "@medusajs/admin-sdk": "2.12.2",
    "@medusajs/cli": "2.12.2",
    "@medusajs/framework": "2.12.2",
    "@medusajs/medusa": "2.12.2"
  },
  "devDependencies": {
    "@medusajs/test-utils": "2.12.2",
    "@swc/core": "^1.7.28",
    "@swc/jest": "^0.2.36",
    "@types/jest": "^29.5.13",
    "@types/node": "^20.12.11",
    "@types/react": "^18.3.2",
    "@types/react-dom": "^18.2.25",
    "jest": "^29.7.0",
    "prop-types": "^15.8.1",
    "react": "^18.3.1",
    "react-dom": "^18.3.1",
    "ts-node": "^10.9.2",
    "typescript": "^5.6.2",
    "vite": "^5.4.14",
    "yalc": "^1.0.0-pre.53"
  },
  "engines": {
    "node": ">=20"
  }
}

Node.js version

v20.2.0

Database and its version

PostgreSQL 16.2

Operating system name and version

MacOS Tahoe - 26.1

Browser name

Chrome

What happended?

When trying to create the following two promotion types:

• Amount off order
• Percentage off order

The max_quantity field is hidden (as expected) on the details tab, however, its value (1) is being sent in the API request and causing the error "application_method.max_quantity is not allowed to be set for allocation (across)"

{
    "code": "FREE",
    "type": "standard",
    "status": "draft",
    "limit": 999,
    "rules": [
        {
            "operator": "eq",
            "attribute": "sales_channel_id",
            "values": "XXX"
        }
    ],
    "application_method": {
        "allocation": "across",
        "value": 100,
        "max_quantity": 1, <-- ERROR HERE
        "type": "percentage",
        "target_type": "order",
        "target_rules": [],
        "buy_rules": []
    },
    "is_tax_inclusive": false,
    "is_automatic": false
}

Expected behavior

Go through the promotion wizard and successfully create 'off order' promotions.

Actual behavior

When clicking save in the promotion wizard when trying to create an 'off order' an error occurs "application_method.max_quantity is not allowed to be set for allocation (across)".

Link to reproduction repo

It's an admin issue - currently using Medusa Cloud hosting - https://github.com/medusajs/medusa

[fPolic]

Thanks for the report @dan-long-dev.
Managed to reproduce this when changing between "off product" promotion types a few times before proceeding to the next screen.
Will open a PR with a fix!

[dan-long-dev]

Amazing, thanks @fPolic