If your Customers pays via PayPal for a Level/Subscription but their Level is not updated after a while try to see that everything is working properly following the next cases:

• Set your PayPal Gateway to Live instead of Sandbox.
• Be sure that your Customers actually paid for subscriptions and you’ve really received the required fee into your PayPal Balance.
• Ensure that you didn’t set any manual IPN URL into your PayPal account. You can check that on PayPal Interface -> My Profile -> My Selling Tolls -> Instant payment notifications. UMP informs PayPal which IPN address needs to be used for confirming the payments.
• Ensure that on your Server and Website there is no restriction and enough permission to access the IPN file via URL.  Your IPN URL is based on your plugin path and ipn file:yourwebsite.com/?ihc_action=paypal
  (before v.4.3): yourwebsite.com/wp-content/plugins/indeed-membership-pro/paypal_ipn.php
• If you are not able to access your IPN file via browser or you get any error (like 500 server error) means that the PayPal API can not access either. Get in touch with your Hosting Provider and ask about this restriction.
• Check if your cURL library is properly installed on your Server and there is not a SSL problem. Contact your hosting provider for more details.
• Ensure that your Primary PayPal currency exactly the same with the currency set into UMP system. Otherwise, your transaction from Paypal will not be managed automatically.
• Check your Transactions tab to see if any transaction was stored but no Level updates.