Click on your profile button located on the upper right. It has the first letter of your Last Name.

Click on Account Settings.

Now that you’ve entered your Account Settings, you’ll find on the bottom right the “Change my plan” button, click on it.

You’re automatically on the monthly options, be sure to press the Yearly button at the top.

If it appears in white, it means that you pressed it right.

Now that you’re on the yearly options, select the Pro Plan.