Paypal REST API订阅集成错误

我正在尝试使用以下文档通过PayPalRESTAPI集成Paypal订阅 （基本整合）

步骤1（自动化成功） 步骤2（成功创建产品） 步骤3（成功创建计划）

步骤4（创建订阅失败）
它看起来像是通过JavaScript SDK中的智能支付按钮工作的。但是通过RESTAPI

curl -v -k -X POST https://api.sandbox.paypal.com/v1/billing/subscriptions \
  -H "Accept: application/json" \
  -H "Authorization: Bearer Access-Token" \
  -H "PayPal-Request-Id: SUBSCRIPTION-21092020-001" \
  -H "Prefer: return=representation" \
  -H "Content-Type: application/json" \
  -d '{
        "plan_id": "P-4ML8771254154362WXNWU5BC",
        "start_time": "2020-11-01T00:00:00Z",
        "quantity": "20",
        "shipping_amount": {
            "currency_code": "USD",
            "value": "10.00"
        },
        "subscriber": {
          "name": {
              "given_name": "John",
              "surname": "Doe"
          },
          "email_address": "customer@example.com",
          "shipping_address": {
              "name": {
                  "full_name": "John Doe"
              },
              "address": {
                  "address_line_1": "2211 N First Street",
                  "address_line_2": "Building 17",
                  "admin_area_2": "San Jose",
                  "admin_area_1": "CA",
                  "postal_code": "95131",
                  "country_code": "US"
              }
          }
        },
        "application_context": {
          "brand_name": "example",
          "locale": "en-US",
          "shipping_preference": "SET_PROVIDED_ADDRESS",
          "user_action": "SUBSCRIBE_NOW",
          "payment_method": {
              "payer_selected": "PAYPAL",
              "payee_preferred": "IMMEDIATE_PAYMENT_REQUIRED"
          },
          "return_url": "https://example.com/returnUrl",
          "cancel_url": "https://example.com/cancelUrl"
        }
      }'

我明白了

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我尝试了所有可能的方法，但我不知道如何调试这个问题，也不知道创建订阅请求中缺少了什么。谢谢大家!

请尝试将PayPal请求Id作为唯一Id传递（PayPal服务器将其存储为唯一Id），它应该可以工作 欲了解更多详情，请点击链接

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让我知道是否解决了相同的问题，我甚至复制粘贴了API文档中的代码。但是没有运气

{"name":"INVALID_REQUEST","message":"Request is not well-formed, syntactically incorrect, or violates schema.","debug_id":"ec6f365217c37","details":[{"field":"/name","location":"body","issue":"MISSING_REQUIRED_PARAMETER","description":"A required field is missing."},{"field":"/payment_preferences","location":"body","issue":"MISSING_REQUIRED_PARAMETER","description":"A required field is missing."},{"field":"/billing_cycles","location":"body","issue":"MISSING_REQUIRED_PARAMETER","description":"A required field is missing."},{"field":"/product_id","location":"body","issue":"MISSING_REQUIRED_PARAMETER","description":"A required field is missing."}],"links":[{"href":"https://developer.paypal.com/docs/api/v1/billing/subscriptions#INVALID_REQUEST","rel":"information_link","method":"GET"}]}