应用按比例分配、升级和降级
如果您对应用的订阅进行升级或降级，此应用将提醒您同意新的定期应用费用。这是因为 Shopify 一次只允许每个应用拥有一笔定期应用费用。现有的定期应用程序费用将被取消，并由新的费用取代。
当您升级套餐（从较低费用转到较高费用的套餐）时，系统将根据价格差异和账单周期剩余天数，按比例计算费用。例如，如果您以 5.00 美元的套餐开始 30 天的账单周期，然后在账单周期的第 15 天升级到 15.00 美元的套餐，则需要支付 5.00 美元 +（15.00 美元 - 5.00 美元）*（15/30） = 10.00 美元。
如果您降级套餐（从较高费用转到较低费用的套餐），则系统会基于价格和账单周期内的剩余天数自动为您提供应用程序信用额度。您以后在 Shopify 购买任何应用程序时都可以使用此应用程序信用额度。
请求应用退款或抵扣额
如果您想为从 Shopify 应用商店购买的应用请求退款或申请抵扣额，您可以使用"获取支持"按钮联系该应用的开发人员。开发人员可能会视具体情况批准或拒绝您的退款请求。请查看应用的产品页面或开发人员的主页，了解他们是否有退款政策。
如果应用费用是使用 Shopify 处理的，则应用的开发人员可以给您退款或提供抵免额。抵免额可用于以后任何 Shopify 应用商店的购买。应用于 Shopify 应用商店购买的所有抵免额都记录在订阅账单中。
如果应用费用是在 Shopify 外部处理的，则开发人员可以按照所使用的原始付款方式处理退款。
步骤：
访问 Shopify 应用商店并搜索应用。
点击应用，然后点击获取支持。
输入您的信息和消息，然后点击发送消息。
回复将会发送到与您的登录信息关联的电子邮件地址。
备注：如果您不想再使用应用，则可以从商店中卸载应用。
应用计费常见问题
为什么看起来我拖欠了费用？
安装应用后，您会立即在账户中看到应用费用，但在收到 30 天周期的账单之前，无需支付费用。
为什么在同一个 30 天账单周期内向我收取了两次费用？
如果您在 Shopify 周期结束后但在应用账单周期重置之前产生应用使用费，则这些使用费将显示在下次 Shopify 订阅账单上。
为什么对我的应用费用收取税费？
如果您居住的地区需要 Shopify 收取任何账户费用的税费，则这些费用会显示在您的 Shopify 发票中。 这可能包括您的应用费用。
Shopify商户官网原文详情：
App prorating, upgrades, and downgrades
If you upgrade or downgrade your subscription with an app, then the app will prompt you to agree to a new recurring app charge. This is because Shopify allows each app only one recurring app charge to be enabled at a time. The existing recurring application charge will be canceled and replaced by the new charge.
When you upgrade your plan by moving from a less expensive charge to a more expensive charge, the charge is prorated based on the difference in price and the number of days remaining in the billing cycle. For example, if you begin a 30-day billing cycle on a $5.00 plan, and then upgrade to a $15.00 plan on day 15 of the billing cycle, you'd be charged $5.00 + ($15.00 - $5.00) * (15/30) = $10.00 USD.
If you downgrade your plan by moving from a more expensive charge to a less expensive charge, then you're automatically offered an application credit based on the difference in price and the number of days remaining in the billing cycle. This application credit can be used towards any future application purchase on Shopify.
Request an app refund or credit
If you want to request a refund or credit for an app that you purchased from the Shopify App Store, then you can use the Get support button to contact the app's developer. The developer might approve or deny your refund request, depending on the circumstances. Check the app's listing page or the developer's home page to see if they have a refund policy.
If the app charge was processed using Shopify, then the app's developer can issue you a refund or give you a credit. Credits will be applied towards any future Shopify App Store purchases. All credits that are applied to Shopify App Store purchases are documented on your subscription bill.
If the app charge was processed outside of Shopify, then the developer can process a refund according to the original payment method used.
Steps:
Visit the Shopify App Store and search for the app.
Click on the app, then click Get support.
Enter your information and a message, then click Send message.
Replies will be sent to the email address associated with your login.
App billing FAQ
Why does it look like I'm being charged in arrears?
You'll see app charges on your account as soon as you install an app, but fees won't be due until you receive your 30-day bill.
Why am I being billed two times for the same 30 day billing cycle?
If you incur app usage charges after the Shopify cycle has ended but before the apps billing cycle resets, then those usage charges will appear on the next Shopify subscription bill.
Why are taxes applied to my app charges?
If you live in a region where Shopify is required to charge taxes on any of your account charges, these charges appear in your Shopify invoice. This might include your app charges.
文章内容来源：Shopify商户官方网站
