Remove "All Day" in Widget

Hey! I really like the plugin. This is my problem:
I use the widget für displaying upcoming events in the sidebar. There are many events having no concrete starting time. So the plugin displays “All Day” (“Ganzt?gig:” in german) in front of the event title.
How can I simply remove the “All Day” string?
I tried to remove the translation in the *.po file – No success.

Thanks for your help:)
Max

Site: https://hammerhuetter-schule.de

https://www.ads-software.com/plugins/event-organiser/