Last transaction is pending. Reason: Customer did not register or confirm his/her email yet

Hello! I have seen this question has been asked in the past but the resolutions on the other answers didn't work for me.

Using paypal express - single payment in sandbox mode. I register as a new user, press the subscribe button, I go to paypal and use my sandbox account. I pay for the subscription and then I get taken back to the site, I am directed to the page for completed subscriptions but I am never assigned a subscription level. It appears the paypal transaction is working as it is showing up in membership under pending transactions so then the user doesn't get assigned a subscription even though they paid.

What exactly is going wrong? Is there suppose to be an email that membership sends out to confirm the new users email?

The new user that is created is never sent a new email to confirm their email address.