Hello Maryam,
Thanks for reaching out! I’m sorry to hear about your issue with the EventBrite widget.
Can you give me some very specific event details to which it has happened and when? Some screenshots of how the event is set up would greatly help.
To narrow down the source of the issue please try the following: when the widget disappears again for an event – eventhough it is still supposed to show – deactivate all plugins except for the calendar and ticketing ones and see if the widget reappears.
If the widget becomes visible, then likely there is a conflicting plugin that makes this happen. If the widget doesn’t appear, then we need to dig further.
To eliminate an issue caused by differing timezones you can try the following: when the widget disappears, then change the timezone of the event backwards. (E.x. if the event timezone was New York, then change it to Los Angeles.) Check if the widget re-appears with the different timezone. If you cannot change the timezone of the event, then change the timezone of WordPress under Settings > General.
Looking forward to helping you fix this.
Cheers,
Andras