Hi Mary 🙂
Though you’ve posted in the Events Calendar PRO area and have a valid license for that plugin, I see you also have a Community Events license. Does your question apply to that plugin (ie, frontend submissions via Community Events)? If so, the following snippet may be useful for you:
https://gist.github.com/barryhughes/9317e5dbecbde0254e6c6bf14ef38b51
This could be added either to a custom plugin (preferred) or else to your theme’s functions.php file.
You can modify it to suit your needs, but by default it tries to stop users from creating titles longer than 65 characters. Let me know if that helps, or any other details that will help me understand your problem if not.
Thanks!