Good afternoon Kirill and welcome to the Events Calendar Support forum
Thank you for reaching out to us.
I would love to help you with this topic.
It sounds like you have entered the license key for Pro in the spot reserved for Event Aggregator (one of our services).
Here is how to fix this:
- Completely remove all license keys from the Events -> Settings -> Licenses
- Make sure that both the Events Calendar and the Events Calendar Pro are activated
- Go back to Events -> Settings -> Licenses look for the Events Calendar Pro’s license key placeholder and enter the key there
If that does not work for some reason.
Could you please send me a copy of the latest version of your WordPress theme and child theme via a link to a .zip file link (stored Dropbox or Google Drive) so that I can run some tests on my end ? I recommend a private reply for that purpose.
Please ensure you are using the latest files as found on your actual website.
This way I will get access to any updates or customizations you might have made.
Let me know how that goes.
Best regards,
Geoff B.