curl --request POST \
  --url https://api.qonversion.io/v3/users/{id}/properties \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
[
  {
    "key": "valid_key",
    "value": "valid_value"
  },
  {
    "key": "invalid key",
    "value": "value"
  }
]
'

{
  "savedProperties": [
    {
      "key": "valid_key",
      "value": "valid_value"
    }
  ],
  "propertyErrors": [
    {
      "key": "invalid key",
      "error": "Property key: invalid key. Error: invalid key format."
    }
  ]
}