Hello Tony,
thanks for your response.
I'm still working with jEvents 3.4.48, Joomla version 3.9.5.
What do you mean with "test in the backend"? what and where can I test it in the backend?
Maybe the issue is my template, so I'm working now on an other template and also with jEvents 3.4.5.
I'm wondering because this error only occurs when I'm not entering the enddate field, only changing the startdate field, because it seems to be changing the enddate automatically. So the users are moving directly to SAVE.
If you would like to have a look:
thanks
Kalle