I renewed my license just now, but in my WordPress backend, I still get the message "Your free upgrade period has expired. To get automatic update, please renew your license" and hence can not update the plugin.
Firstly, please make sure you have used the email address of your existing account to renew or upgrade your license, otherwise a new account will be created. If this has happened to you, please contact our support team at firstname.lastname@example.org, we will merge your renewal to your existing account.
WordPress caches all plugin information. After your license has been renewed, in your WordPress backend, you may still get the message "Automatic update is unavailable for this plugin. Your free upgrade period has expired. To get automatic update, please renew your license.".
To clear the cache and speed up the process, in your WordPress backend, left menu, click the menu item Dashboard -> Updates, then click the link "Check Again". You may need to click the link several times.
If it's still not working, please log out of your WordPress, wait for several hours and login again.