You can check your subscriptions from the Office365 by logging in at https://www.office.com/
Once logged in, click on your avatar in the top right and select the 'View account' option.
This will take you to your account overview with a navigation pane on the left hand side.
The bottom option in the list will allow you to review Subscriptions on your account:
Scroll down to the bottom of the list, where you will see PowerBI Pro, should you have the license linked to your account:
For more information regarding PowerBI licenses, please visit: