Sorry to hear this Jan! And thanks for your patience over the weekend. 😀
I cannot recreate this issue on my own site, so it is probably due to some CSS issues arising from your theme (or possibly another plugin on your site).
With this in mind, to help me help you can you provide the following details?
1. Post your site’s complete, un-edited system information using the “Sharing information manually” steps outlined in this article: https://theeventscalendar.com/knowledgebase/sharing-sys-info/
2. Post a URL to a single event on your site where I can see that map/tickets display issue in your screenshot firsthand.
I’ll review your system info and look at the event live, and see what I can recommend from there. 😀
— George