Hey!
Thank you for reaching out to us!
When we try to make the site compatible with all themes and plugins sometimes is not possible due the large number, but we are going to see if we can find the problem you are facing on your site.
I did a check on it and seems like on the events page THÈMES, button is not displayed but it’s on the first link so that might be a hint on your theme by looking on how this button is being added to the menu.
One thing you can do as well is, play around with the different type of settings of display of the Events Calendar Plugin to test if any is causing the issue you can change the settings at:
Events > Settings > Display
And look for ‘Default stylesheet used for events templates‘, The plugin does not add any new menu items on menus so it shouldn’t be a problem there.
Another useful link might be to take a look at the guides for conflicts, to see if this is not being caused by any other plugin.
Please let me know if you have any other questions about this issue or if there’s anything else I can do for you.
Thanks,
Crisoforo