To see your invoices, you'll need to start by logging in to your account. Click on the three dots shown at the top right corner of the screen. Choose My Account.
Click Edit billing info in the Billing info section.
Now you'll reach the page containing your account information. Below your subscription details, you'll see the Invoices section.
Here's where you can find your recent invoices listed, with a download icon at the end of the row where you can download individual invoices. Click All Invoices if you're looking to see an older one.