title: Stripe Subscription Upgrade Causing Unwanted Invoice Item
body: <p>I want to upgrade my user's package via Stripe API, from &quot;59$ per month&quot; package to &quot;109$ per month&quot; package and <strong>immediately</strong> charge (109-59=50$) / invoice the user. This is how I am doing:</p>
  <pre><code>const subscription: Stripe.Subscription = await this.stripe.subscriptions.retrieve(
              EXISTING SUBSCRIPTION ID,
          );
  await this.stripe.subscriptions.update(EXISTING SUBSCRIPTION ID, {
          cancel_at_period_end: false,
          proration_behavior: 'create_prorations',
          items: [{
              id: subscription.items.data[0].id,
              price: PRICE ID OF NEW PACKAGE,
          }]
      });
  </code></pre>
  <p>This is upgrading my user's package successfully but the invoice looks like this:</p>
  <p><a href="https://i.stack.imgur.com/DAokK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DAokK.png" alt="enter image description here" /></a></p>
  <p>The part &quot;JAN 28 - FEB 28&quot; is correct. It's subtotal is 50$ that is correct. But why it's also automatically subscribing for the next period (FED 28 - MAR 28). This shouldn't be in the invoice. And the invoice total should be 50$ not 159$.</p>