You may find information about your current subscription on your Speechify app's setting page.
To go to settings, please click the 👤 icon at the upper left corner of the page. Then you should see a ⚙️ icon on the top right corner. Clicking on that takes you to Settings.
On the Settings page, click your name and this should show you the following info:
Email address associated with your Speechify account
Date you started your membership or current plan
Type of subscription plan
Date your subscription plan renews