event posts appearing twice in calendar

Hello,

on my local webserver (https://localhost) I run a fresh WordPress installation and installed just the free Ashe-Theme from ‘WP Royal’ and your ‘Event post’ plugin.
I created two simple posts as events and as you see on this screenshot-link https://www.dropbox.com/s/ehsiv5oo7o3k9a4/event_post_cal.png, the events with their post images appears twice on plugin calendar.
I’m not really sure if that’s the desired behaviour but if not, do you have an idea, why the this happens and how to fix it to make the events just appearing once on calendar?
So far I found no solution by myself so any help would be appreciated.
Thanks in advance.

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