Error after upgrading to 3.4.45

Hi
http://www.javeaguide.com/calendar-of-events-fiestas-in-javea
Running
Joomla 3.8.5
JEvents 3.4.45

After upgrading to 3.4.45 I now get an error when I try to edit an existing event or add a new one

An error has occurred.
0 Cannot unset string offsets
See screen capture
Screenshot of error
Hopefully this can be rectified without too much trouble
Best regards
Ashley