curl --request PATCH \
  --url https://api-m.sandbox.paypal.com/v1/commerce/billing/subscriptions/{external_subscription_id}/entitlements \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "entitlements": [
    {
      "feature_code": "seats",
      "feature_privilege_values": {
        "max": 250,
        "max_admins": 25,
        "guest_access": true
      }
    },
    {
      "feature_code": "sso",
      "feature_privilege_values": {
        "provider": "saml"
      }
    }
  ]
}
'

{
  "entitlements": [
    {
      "feature_code": "seats",
      "name": "Number of seats",
      "description": "Number of users of the account",
      "feature_privileges": [
        {
          "code": "max",
          "name": "Maximum",
          "value_type": "INTEGER",
          "value": 250,
          "plan_value": 100,
          "override_value": 250
        },
        {
          "code": "max_admins",
          "name": "Max Admins",
          "value_type": "INTEGER",
          "value": 25,
          "plan_value": 10,
          "override_value": 25
        },
        {
          "code": "root",
          "name": "Allow root user",
          "value_type": "BOOLEAN",
          "value": true,
          "plan_value": true,
          "override_value": null
        },
        {
          "code": "guest_access",
          "name": "Allow guest access",
          "value_type": "BOOLEAN",
          "value": true,
          "plan_value": false,
          "override_value": true
        }
      ]
    },
    {
      "feature_code": "sso",
      "name": "Single Sign-On",
      "description": "SSO authentication configuration",
      "feature_privileges": [
        {
          "code": "enabled",
          "name": "SSO Enabled",
          "value_type": "BOOLEAN",
          "value": true,
          "plan_value": true,
          "override_value": null
        },
        {
          "code": "provider",
          "name": "SSO Provider",
          "value_type": "SELECT",
          "value": "saml",
          "plan_value": "google",
          "override_value": "saml",
          "config": {
            "select_options": [
              "google",
              "okta",
              "azure",
              "saml"
            ]
          }
        }
      ]
    }
  ]
}