In order to activate Modern Events Calendar Pro license, you no longer need to go to the Settings menu. Now, you can find it on the main menu under the M.E. Calendar.
How to Activate Modern Events Calendar Pro License?

To update MEC, enter your purchased code (which you can find in your dashboard area) in the field and hit the green Submit button.
If, by any chance, you could not activate MEC, visit this link.To access the license keys for the activation of the Modern Events Calendar, navigate to Webnus download panel, and click on View Licenses. Then on the new page, you can see the license key.

Note: If you activate MEC on the localhost (or another domain), you should delete the plugin completely before activating it with the same purchase on a new domain.
If you want to change your license domain, you should go to the license key menu and click on Manage Site and follow the instructions for changing the domain.
Now deactivate the license for the old site and remove MEC and its license key from it.
Then go to MEC main menu in your new website WordPress dashboard and enter the license to activate the new domain.
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