Hi Carolee,
Thanks so much for reaching out!
As a first troubleshooting step, could you please provide us with your complete system information in a private reply using the instructions found in the following link?
https://theeventscalendar.com/knowledgebase/sharing-sys-info/
Are you only seeing this Page ID on Events pages, or on all pages?
Do you still see this page ID if you switch to a default WordPress theme, like Twentyseventeen?
Can you provide me with a link to a page that has the page ID included?
Let me know if you have any other questions in the meantime!
Thanks,
Jaime