We're sorry for the delayed response and inconvenience caused. Yes, you can cancel the Adobe ExportPDF service purchased through the play store.
Subscriptions that you purchase via Adobe Reader for Android are paid through Google's App Store. For the cancellation, you have to contact Google. Cancel or change a subscription on Google Play - Android - Google Play Help
You can also refer to Cancel your membership or subscription | Adobe Acrobat, Document Cloud PDF services
Feel free to update this discussion for any further assistance.